Algebraic Triangles

In this worksheet, students form and solve equations by adding together the algebraic angles shown in each triangle.

Key stage: KS 3

Curriculum topic: Geometry and Measures

Curriculum subtopic: Interpret Mathematical Relationships Algebraically/Geometrically

Difficulty level:

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Worksheet Overview

The angles in a triangle add to 180º.

This is no different when the angles are algebraic expressions.

Example

Form an equation from the angles shown in this triangle and solve it to find the value of a.

Answer

The sum of the angles = 180

a + 10 + a - 37 + a = 180

We simplify and solve this equation as follows:

3a - 27 = 180

3a = 207

a = 207 ÷ 3 = 69

a = 69

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Preview activity

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