Measurements and Geometry

Reflection and Congruence - Lines of symmetry in plane figures
Reflection and Congruence - Properties of reflection

By the end of the lesson, the learner should be able to:

- Identify lines of symmetry in plane figures
- Determine the number of lines of symmetry
- Recognize symmetry in nature and art

- Collect objects from environment and identify lines of symmetry
- Fold paper cut-outs to locate lines of symmetry
- Discuss symmetry in nature and architecture

How do we identify lines of symmetry?

- Mentor Core Mathematics Grade 10 pg. 75
- Paper cut-outs
- Plane mirrors
- Objects from environment
- Mentor Core Mathematics Grade 10 pg. 78
- Tracing paper
- Graph papers

- Observation - Oral questions - Practical activities

Measurements and Geometry

Reflection and Congruence - Reflection on plane surface
Reflection and Congruence - Reflection on Cartesian plane (x-axis and y-axis)

By the end of the lesson, the learner should be able to:

- Draw an image given object and mirror line on plane surface
- Construct perpendicular bisectors accurately
- Apply reflection in creating symmetric designs

- Draw plane figures and mirror lines on paper
- Use properties of reflection to locate images
- Create symmetric patterns using reflection

How do we construct images under reflection?

- Mentor Core Mathematics Grade 10 pg. 79
- Plain paper
- Geometrical instruments
- Rulers
- Mentor Core Mathematics Grade 10 pg. 82
- Graph papers
- Geometrical set
- Calculators

- Practical assessment - Written tests - Observation

Measurements and Geometry

Reflection and Congruence - Reflection along lines y=x and y=-x
Reflection and Congruence - Reflection along other lines

By the end of the lesson, the learner should be able to:

- Draw images after reflection along y=x and y=-x
- Determine image coordinates accurately
- Apply knowledge in solving transformation problems

- Draw objects and reflect along y=x
- Reflect along y=-x
- Compare results and establish patterns

What happens to coordinates when reflecting along y=x?

- Mentor Core Mathematics Grade 10 pg. 84
- Graph papers
- Geometrical instruments
- Rulers
- Mentor Core Mathematics Grade 10 pg. 85
- Geometrical set
- Calculators

- Written assignments - Practical work - Observation

Measurements and Geometry

Reflection and Congruence - Determining equation of mirror line
Reflection and Congruence - Congruence tests (SSS and SAS)

By the end of the lesson, the learner should be able to:

- Determine equation of mirror line given object and image
- Construct perpendicular bisectors accurately
- Apply knowledge in solving problems

- Join corresponding points and construct perpendicular bisectors
- Determine gradients and y-intercepts
- Form equations of mirror lines

How do we find the equation of a mirror line?

- Mentor Core Mathematics Grade 10 pg. 86
- Graph papers
- Geometrical instruments
- Calculators
- Mentor Core Mathematics Grade 10 pg. 89
- Paper cut-outs
- Rulers

- Written assignments - Practical assessment - Oral questions

Measurements and Geometry

Reflection and Congruence - Congruence tests (ASA and RHS)
Reflection and Congruence - Applications in real life

By the end of the lesson, the learner should be able to:

- Carry out congruence tests using ASA and RHS
- Prove triangles are congruent
- Apply congruence in geometric proofs

- Use triangles to establish ASA congruence
- Test for RHS congruence in right-angled triangles
- Solve problems involving congruence

How do we prove triangles are congruent?

- Mentor Core Mathematics Grade 10 pg. 91
- Paper cut-outs
- Protractors
- Rulers
- Mentor Core Mathematics Grade 10 pg. 95
- Plane mirrors
- Digital devices
- Reference materials

- Written assignments - Class exercises - Oral questions

Measurements and Geometry

Rotation - Properties of rotation
Rotation - Rotation on plane surface

By the end of the lesson, the learner should be able to:

- Determine properties of rotation
- Demonstrate rotation using a clock
- Relate rotation to movement of clock hands and wheels

- Use an improvised clock to demonstrate rotation
- Discuss movement of minute and hour hands
- Generate properties of rotation

What are the properties of rotation?

- Mentor Core Mathematics Grade 10 pg. 97
- Improvised clock
- Protractors
- Paper cut-outs
- Mentor Core Mathematics Grade 10 pg. 99
- Plain paper
- Rulers
- Compasses

- Oral questions - Observation - Written assignments

Measurements and Geometry

Rotation - Rotation through ±90° about origin
Rotation - Rotation through ±180° about origin

By the end of the lesson, the learner should be able to:

- Rotate objects through ±90° about the origin
- State coordinates of images correctly
- Recognize patterns in coordinate changes

- Plot objects on Cartesian plane
- Rotate through +90° and -90° about (0,0)
- Record and compare coordinates

How do coordinates change under rotation through 90°?

- Mentor Core Mathematics Grade 10 pg. 103
- Graph papers
- Geometrical set
- Calculators
- Geometrical instruments

- Written assignments - Class exercises - Oral questions

Measurements and Geometry

Rotation - Rotation about other centres
Rotation - Finding centre and angle of rotation

By the end of the lesson, the learner should be able to:

- Rotate objects about centres other than origin
- Construct rotations accurately
- Solve rotation problems involving various centres

- Rotate objects about various centres
- Use construction methods
- Practice with different angles and centres

How do we rotate about centres other than origin?

- Mentor Core Mathematics Grade 10 pg. 105
- Graph papers
- Geometrical set
- Protractors
- Mentor Core Mathematics Grade 10 pg. 106
- Geometrical instruments

- Written assignments - Practical assessment - Oral questions

Measurements and Geometry

Rotation - Rotational symmetry of plane figures
Rotation - Axis and order of rotational symmetry in solids

By the end of the lesson, the learner should be able to:

- Determine order of rotational symmetry of plane figures
- Use paper cut-outs to demonstrate rotational symmetry
- Identify rotational symmetry in logos and designs

- Use paper cut-outs to locate points of symmetry
- Establish order of rotational symmetry
- Discuss symmetry in logos and patterns

What is the order of rotational symmetry?

- Mentor Core Mathematics Grade 10 pg. 110
- Paper cut-outs
- Pins
- Manila paper
- Mentor Core Mathematics Grade 10 pg. 113
- Models of solids
- Objects from environment

- Oral questions - Practical work - Written assignments

Measurements and Geometry

Rotation - Deducing congruence from rotation
Trigonometry 1 - Reading tangent from tables

By the end of the lesson, the learner should be able to:

- Deduce congruence from rotation
- Identify type of congruence in rotation
- Apply rotation and congruence in problem solving

- Use objects and images to identify congruence
- Distinguish direct and indirect congruence
- Solve problems involving rotation and congruence

What type of congruence results from rotation?

- Mentor Core Mathematics Grade 10 pg. 115
- Graph papers
- Geometrical instruments
- Digital devices
- Mentor Core Mathematics Grade 10 pg. 120
- Mathematical tables
- Calculators

- Written assignments - Class exercises - Observation

Measurements and Geometry

Trigonometry 1 - Reading sine and cosine from tables
Trigonometry 1 - Using calculators for trigonometric ratios

By the end of the lesson, the learner should be able to:

- Determine sine and cosine of acute angles from tables
- Use mean difference correctly
- Apply sine and cosine in solving triangles

- Read sine values from tables
- Read cosine values (subtracting mean difference)
- Practice finding angles given ratios

How do we read sine and cosine from tables?

- Mentor Core Mathematics Grade 10 pg. 122
- Mathematical tables
- Calculators
- Mentor Core Mathematics Grade 10 pg. 126
- Scientific calculators
- Mathematical tables

- Written assignments - Practical work - Observation

Measurements and Geometry

Trigonometry 1 - Complementary angle relationships
Trigonometry 1 - Relating sine, cosine and tangent

By the end of the lesson, the learner should be able to:

- Relate sines and cosines of complementary angles
- Prove that sin θ = cos(90°-θ)
- Apply relationships in solving equations

- Generate table of complementary angles
- Compare sines and cosines
- Establish sin θ = cos(90°-θ)

What is the relationship between sine and cosine of complementary angles?

- Mentor Core Mathematics Grade 10 pg. 128
- Mathematical tables
- Calculators
- Mentor Core Mathematics Grade 10 pg. 129

- Written assignments - Class exercises - Observation

Measurements and Geometry

Trigonometry 1 - Ratios of 45°
Trigonometry 1 - Ratios of 30° and 60°

By the end of the lesson, the learner should be able to:

- Determine trigonometric ratios of 45° using triangles
- Derive exact values without tables
- Apply in solving problems with exact values

- Draw isosceles right-angled triangle
- Calculate hypotenuse using Pythagoras
- Derive sin 45°, cos 45°, tan 45°

How do we find exact values of trigonometric ratios?

- Mentor Core Mathematics Grade 10 pg. 130
- Geometrical instruments
- Rulers
- Mentor Core Mathematics Grade 10 pg. 131

- Written assignments - Practical work - Oral questions

Measurements and Geometry

Trigonometry 1 - Problems involving special angles
Trigonometry 1 - Angle of elevation

By the end of the lesson, the learner should be able to:

- Solve problems using special angle ratios
- Simplify expressions with special angles
- Apply special angles in construction

- Solve problems without tables or calculators
- Simplify trigonometric expressions
- Apply to practical situations

How do we apply special angle ratios?

- Mentor Core Mathematics Grade 10 pg. 132
- Reference materials
- Calculators
- Mentor Core Mathematics Grade 10 pg. 133
- Clinometer
- Measuring tape

- Written assignments - Oral questions - Class exercises

Measurements and Geometry

Trigonometry 1 - Angle of depression
Trigonometry 1 - Applications in real life

By the end of the lesson, the learner should be able to:

- Define angle of depression
- Solve problems involving angles of depression
- Apply to navigation and surveying

- Demonstrate angles of depression
- Sketch diagrams correctly
- Solve problems involving depression

What is angle of depression?

- Mentor Core Mathematics Grade 10 pg. 134
- Clinometer
- Digital devices
- Reference materials
- Mentor Core Mathematics Grade 10 pg. 136
- Reference books
- Calculators

- Written assignments - Practical work - Observation

Measurements and Geometry

Area of Polygons - Deriving area formula
Area of Polygons - Calculating area using Area = ½abSinC

By the end of the lesson, the learner should be able to:

- Derive formula for area of triangle given two sides and included angle
- Use trigonometric ratios in derivation
- Apply formula Area = ½abSinC

- Use trigonometric ratios to derive formula
- Discuss in groups and generate formula
- Practice using the formula

How do we derive the area formula using trigonometry?

- Mentor Core Mathematics Grade 10 pg. 137
- Geometrical instruments
- Calculators
- Mentor Core Mathematics Grade 10 pg. 138
- Calculators
- Mathematical tables

- Written assignments - Class exercises - Observation

Measurements and Geometry

Area of Polygons - Heron's formula
Area of Polygons - Area of rhombus

By the end of the lesson, the learner should be able to:

- Determine area of triangle using Heron's formula
- Calculate semi-perimeter correctly
- Apply formula to triangles given three sides

- Calculate semi-perimeter
- Apply Heron's formula
- Compare with other methods

How do we use Heron's formula?

- Mentor Core Mathematics Grade 10 pg. 139
- Calculators
- Reference materials
- Mentor Core Mathematics Grade 10 pg. 143
- Models of rhombus
- Calculators

- Written assignments - Class exercises - Observation

Measurements and Geometry

Area of Polygons - Area of parallelogram and trapezium
Area of Polygons - Area of heptagon

By the end of the lesson, the learner should be able to:

- Calculate area of parallelogram using base × height
- Calculate area of trapezium
- Apply formulas to practical situations

- Calculate areas of parallelograms
- Calculate areas of trapeziums
- Identify shapes in environment

How do we calculate areas of parallelograms and trapeziums?

- Mentor Core Mathematics Grade 10 pg. 147
- Geometrical instruments
- Calculators
- Mentor Core Mathematics Grade 10 pg. 152
- Paper cut-outs
- Calculators
- Protractors

- Written assignments - Class exercises - Observation

Measurements and Geometry

Area of Polygons - Area of octagon
Area of Polygons - Irregular polygons

By the end of the lesson, the learner should be able to:

- Calculate area of regular octagon
- Use formula involving central angles
- Connect to real objects like stop signs

- Divide octagon into 8 triangles
- Calculate central angle (45°)
- Calculate total area

How do we calculate the area of an octagon?

- Mentor Core Mathematics Grade 10 pg. 156
- Paper cut-outs
- Calculators
- Reference materials
- Mentor Core Mathematics Grade 10 pg. 159
- Geometrical instruments
- Calculators

- Written assignments - Class exercises - Observation

Measurements and Geometry

Area of Polygons - Real-life applications
Area of a Part of a Circle - Annulus

By the end of the lesson, the learner should be able to:

- Apply area of polygons to real-life situations
- Solve problems involving land and flooring
- Relate to careers in architecture and surveying

- Solve real-life problems
- Calculate areas of compound shapes
- Discuss applications in various careers

Where do we use area of polygons in real life?

- Mentor Core Mathematics Grade 10 pg. 163
- Reference materials
- Digital devices
- Mentor Core Mathematics Grade 10 pg. 166
- Compasses
- Calculators

- Written assignments - Project assessment - Observation

Measurements and Geometry

Area of a Part of a Circle - Area of sector
Area of a Part of a Circle - Annular sector

By the end of the lesson, the learner should be able to:

- Calculate area of sector of a circle
- Use formula Area = (θ/360°)πr²
- Apply to pizza slices and pie charts

- Use paper cut-outs to make sectors
- Calculate area using formula
- Solve problems involving sectors

How do we calculate the area of a sector?

- Mentor Core Mathematics Grade 10 pg. 167
- Paper
- Scissors
- Compasses
- Calculators
- Mentor Core Mathematics Grade 10 pg. 170
- Diagrams
- Calculators
- Reference materials

- Written assignments - Practical work - Observation

Measurements and Geometry

Area of a Part of a Circle - Segment of a circle
Area of a Part of a Circle - Problems on segments

By the end of the lesson, the learner should be able to:

- Define segment of a circle
- Calculate area of segment
- Apply formula: Area of sector - Area of triangle

- Draw segments of circles
- Calculate area of sector
- Subtract area of triangle

How do we calculate the area of a segment?

- Mentor Core Mathematics Grade 10 pg. 172
- Geometrical instruments
- Calculators
- Mentor Core Mathematics Grade 10 pg. 174
- Calculators
- Reference materials

- Written assignments - Practical assessment - Observation

Measurements and Geometry

Area of a Part of a Circle - Intersecting circles (introduction)
Area of a Part of a Circle - Calculating common area

By the end of the lesson, the learner should be able to:

- Identify common region between two intersecting circles
- Understand components of common region
- Connect to Venn diagrams and logos

- Draw two intersecting circles
- Identify common region
- Discuss structure of common area

What is the common region between two intersecting circles?

- Mentor Core Mathematics Grade 10 pg. 176
- Compasses
- Rulers
- Graph papers
- Mentor Core Mathematics Grade 10 pg. 177
- Calculators
- Geometrical instruments

- Observation - Oral questions - Written assignments

Measurements and Geometry

Area of a Part of a Circle - Complex problems
Area of a Part of a Circle - Making dartboard and necklaces

By the end of the lesson, the learner should be able to:

- Solve complex problems on intersecting circles
- Calculate shaded regions
- Apply to decorative patterns and designs

- Solve problems involving common regions
- Calculate shaded areas
- Research applications in design

Where do we use intersecting circles in real life?

- Mentor Core Mathematics Grade 10 pg. 179
- Reference materials
- Digital devices
- Calculators
- Mentor Core Mathematics Grade 10 pg. 180
- Cardboard
- Beads
- Paints
- Compasses

- Written assignments - Project work - Oral questions

Measurements and Geometry

Area of a Part of a Circle - Review and assessment
Surface Area and Volume - Rectangular prism

By the end of the lesson, the learner should be able to:

- Solve mixed problems on area of parts of a circle
- Apply all concepts learned
- Evaluate understanding of the sub-strand

- Review all concepts
- Solve mixed problems
- Assess understanding

How well can we apply area concepts?

- Mentor Core Mathematics Grade 10 pg. 181
- Calculators
- Past papers
- Mentor Core Mathematics Grade 10 pg. 182
- Models of prisms
- Nets
- Calculators

- Written tests - Oral questions - Class exercises

Measurements and Geometry

Surface Area and Volume - Triangular and other prisms
Surface Area and Volume - Pyramids

By the end of the lesson, the learner should be able to:

- Calculate surface area of triangular prisms
- Calculate surface area of other prisms
- Apply to tents and buildings

- Draw nets of triangular prisms
- Calculate surface areas
- Solve practical problems

How do we find surface area of triangular prisms?

- Mentor Core Mathematics Grade 10 pg. 185
- Models of prisms
- Calculators
- Mentor Core Mathematics Grade 10 pg. 191
- Models of pyramids

- Written tests - Class exercises - Oral questions

Measurements and Geometry

Surface Area and Volume - Cones
Surface Area and Volume - Frustum of cone

By the end of the lesson, the learner should be able to:

- Calculate surface area of cones
- Use formulas for curved surface and base
- Apply to ice cream cones and funnels

- Make cone models from manila paper
- Calculate curved surface area πrl
- Calculate total surface area

How do we calculate surface area of cones?

- Mentor Core Mathematics Grade 10 pg. 193
- Manila paper
- Compasses
- Calculators
- Mentor Core Mathematics Grade 10 pg. 195
- Cone models
- Scissors

- Written tests - Practical work - Oral questions

Measurements and Geometry

Surface Area and Volume - Frustum of pyramid
Surface Area and Volume - Spheres and hemispheres

By the end of the lesson, the learner should be able to:

- Calculate surface area of frustum of a pyramid
- Apply similar figure properties
- Connect to kitchen worktops and counters

- Sketch original pyramid
- Use similar figures to find dimensions
- Calculate surface area

How do we find surface area of pyramid frustum?

- Mentor Core Mathematics Grade 10 pg. 197
- Models
- Calculators
- Reference materials
- Mentor Core Mathematics Grade 10 pg. 200
- Spherical objects
- Calculators

- Written tests - Class exercises - Oral questions

Measurements and Geometry

Surface Area and Volume - Composite solids
Surface Area and Volume - Volume of cones

By the end of the lesson, the learner should be able to:

- Calculate surface area of composite solids
- Identify component solids
- Apply to real structures and objects

- Identify components of composite solids
- Calculate surface area of each component
- Combine appropriately

How do we find surface area of composite solids?

- Mentor Core Mathematics Grade 10 pg. 202
- Models of composite solids
- Calculators
- Mentor Core Mathematics Grade 10 pg. 205
- Cone and cylinder models
- Sand/water

- Written tests - Project work - Oral questions

Measurements and Geometry

Surface Area and Volume - Volume of prisms and pyramids
Surface Area and Volume - Volume of spheres and hemispheres

By the end of the lesson, the learner should be able to:

- Calculate volume of various prisms
- Calculate volume of pyramids using ⅓Bh
- Apply to buildings and storage

- Calculate volumes of prisms
- Apply pyramid volume formula
- Solve real-life problems

How do we calculate volumes of prisms and pyramids?

- Mentor Core Mathematics Grade 10 pg. 206
- Models of solids
- Calculators
- Mentor Core Mathematics Grade 10 pg. 210
- Spherical objects

- Written tests - Class exercises - Oral questions

Measurements and Geometry

Surface Area and Volume - Volume of frustums
Surface Area and Volume - Composite solids volume

By the end of the lesson, the learner should be able to:

- Calculate volume of frustum of cone and pyramid
- Use similar figure relationships
- Apply to buckets, lampshades and pots

- Calculate volume of original solid
- Subtract volume of cut-off part
- Solve problems involving frustums

How do we calculate volume of a frustum?

- Mentor Core Mathematics Grade 10 pg. 212
- Models
- Calculators
- Reference materials
- Mentor Core Mathematics Grade 10 pg. 216
- Models of composite solids
- Calculators

- Written tests - Class exercises - Oral questions