Question

The angles opposite the congruent sides of an isosceles triangle are congruent. Find the value of x

Answer 1

The diagram above will help us to find x

Note: The angles opposite the congruent sides of an isosceles triangle are congruent.

So we have the other side to be 70 degrees as well (as shown above)

The sum of angle in a triangle is 180 degrees

`\begin{gathered} 70+70+x=180^(\circ) \\ 140^(\circ)+x=180 \\ x=180-140 \\ x=40^(\circ) \end{gathered}`

Therefore, the angle marked x = 40 degrees