Question

The measure of angle 3 is 42 degrees​

Answer 1

Angle one equal 48 degrees

Explanation:

Angle three is equal to 42 degrees. diagonal of that is angle five which would be equal to angle three (42 degrees. We know that the horizontal angle equals 180 degrees and that angle two is 90 degrees. so 180-90 gives us 90, which is the sum of angle 1 and 5. Angle five is 42 degrees. so 90-42 is 48.

Answer 2

angle 1 is equal to 48°
if angle 3 and 2 are known you add them and subtract from 180