iGCSE Mathematics (0580) :E4.1 Use and interpret the geometrical terms.iGCSE Style Questions Paper 2

Question

A regular polygon has an interior angle of 174°.

Find the number of sides of this polygon.

▶️ Answer/Explanation

Solution

60 sides

Use interior angle formula: $(n-2) × 180° = n × 174°$

Expand: $180n – 360 = 174n$

Solve: $6n = 360$ → $n = 60$

Question

The diagram shows triangle ABC.
M is the midpoint of AC.

Triangle ABC is rotated 180° about centre M.
The image and the original triangle together form a quadrilateral ABCD.

(a) Write down the mathematical name of the quadrilateral ABCD.

(b) Find angle BAD.

▶️ Answer/Explanation

Solution

Ans:

(a) Parallelogram (opposite sides equal and parallel)

(b) 68° (180° – 112° from rotation properties)

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