e= 42 degrees
All lines add up to 180 degrees so you subtract the exterior angle, 132 degrees, by 180 to get the difference of 48 degrees in the interior angle. Also since the triangle is a right angle, you know the sum of the other two angles add up to 90 degrees. So 48 plus angle E would have to add up to 90 degrees. Therefore 48 degrees plus angle E, 42 degrees, adds up to 90 degrees.