m∠D = 72° (option A)
Explanation:
The sum of angles in a quadrilateral is 360 degrees
Since a trapezium is a quadrilateral, the sum of angles will be 360 degrees
∠A + ∠B + ∠C + ∠D = 360°
72° + 108° + 108° + ∠D = 360°
288 + ∠D = 360
collect like terms:
∠D = 360 - 288
∠D = 72°
m∠D = 72° (option A)
