Question

I need help with the attached proofing question ASAP!!! You have to prove two angles equal 90 Degrees. Thank you greatly in advance.

Answer 1

angle 1 + angle 2 = 90° because angle 3 is equal to angles 2

To prove angle 1 + angle 2 = 90°

angle DAB is a right angle : Given

line AB is parallel to line CD : Given

angle 3 + angle 2 = 90°

angle 2 = angle 4 ( alternate interior angles)

angle 1 = angle 2 ( alternate interior angles)

Since angle 3 + angle 2 = 90°

and angle 1 = angle 3

we can substitute angle 1 for angle 3

therefore;

angle 1 + angle 2 = 90°

Therefore it has been proved that angle 1 + angle 2 = 90°