Chapter 2.8, Problem 4PSA

To determine

To prove : The congruency of $\angle A=\angle DCE$ is to be proved

Explanation of Solution

Given information : The following information has been given

  $\angle A=\angle ACB$

Formula used : Vertically opposite angles have same value of measurement

Proof : As we know that $\angle ACB$ and $\angle DCE$ are a pair of vertically opposite angles, hence we can say that

  $\angle ACB=\angle DCE$

And,

  $\angle A=\angle ACB$

Thus, from the above two equations, we can say that

  $\angle A=\angle DCE$

Thus, the desired result is proved