Question

What is the measure of ZABD? What is the reason?60° , isosceles triangle theorem48°, equilateral triangle theoremCO 48°, isosceles triangle theorem60° , equilateral triangle theoremB66°DA

Answer 1

Consider the traingle ABD,

The side AB and A are equal means that angle A is equal to angle D.

Determine the angle B of traingle ABD by using angle sum property of triangle.

`\begin{gathered} \angle A+\angle B+\angle D=180^(\circ) \\ 66^(\circ)+66^(\circ)+\angle B=180^(\circ) \\ \angle D=48^(\circ) \end{gathered}`

So angle D is of 48 degree and two sides are equal so isoceles traingle theorem is used for angle measurement. Option C is correct.