Question

Use a ruler and compass only in this question.
Construct the quadrilateral ABCD in which AB = 5 cm, BC = 7 cm and angle ABC = 120°, given that AC is its only line of symmetry.

Answer 1

Steps of construction :
(1) Draw BC = 7 cm and at B make ∠ABC = 120°
(2) With B as centre and radius = 5 cm, cut BX at A.

(3) With A as centre and radius = 5 cm draw an arc and with C as centre and radius = 7 cm draw another arc. The arcs meet at D.
Thus ABCD is the required quadrilateral.