Which of the following pairs of angles is not necessarily congruent

E. and .

Explanation:

According to the figure, we have the following conclusions:

1) and are vertical opposite angles. ()

2) and are internal alternate angles. ()

3) and are corresponding angles. ()

4) and are vertical opposite angles. ()

But, and , since , where is an acute angle and is a right angle, and . Then,

.

Hence, the right answer is E.

the anwser is definetly b. arriving to class right before the test