What this quiz covers

Grade 8 Angles of Triangles Quiz 1 draws its questions at random from 8 questions across these topics:

• Angle Sum of a Triangle
• Classifying Triangles — Isosceles
• Angle Sum — Isosceles Triangle
• Exterior Angle Theorem
• Angles in a Right Triangle
• Algebraic Angles — Equilateral Triangle
• Altitude of an Isosceles Triangle
• Perpendicular Bisector — Isosceles Triangle

Example questions

A sample of the questions you will practise in this quiz. Work them out yourself - the full solution appears after you answer each one.

1. In triangle ABC, the interior angles are \((4x + 10)°\), \((5x + 5)°\) and \(2x°\). What is the value of \(x\)?
2. Triangle DEF has DE = DF (indicated by tick marks) and EF = 10 cm. What type of triangle is DEF?
3. In triangle GHJ, ∠G = 22° and ∠J = 22°. What is the size of angle H?
4. Points J, K, L, M lie on a straight line. Using the exterior angle theorem, what is the value of \(x\)?
5. AD ⊥ BC so ∠ADB = 90°. Given ∠B = 41°, what is the value of angle \(y\) (i.e. ∠BAD)?