Shape and Space 1

2 marks · Easy

A triangle labelled PQR with PQ = QR and angle PQR marked.

(a)

Name the type of triangle shown.

[1 mark]

(b)

If angle x is 40°, calculate the size of angle PRQ.

[1 mark]

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Show answer

(a) Isosceles triangle

(b) 70 degrees

Show mark scheme and worked solution

Marking points

B1 (a) · 1 mark · Names 'isosceles triangle'.

M1 (b) · 0.5 marks · Uses sum of angles in triangle: 180−40=140, halves result for base angles.

A1 (b) · 0.5 marks · Correctly gives 70 degrees as each base angle. (follow-through)

Worked solution

a) The triangle is isosceles since PQ = QR.

So angle PRQ = 70°.