Question

Proof box

Statement


Reason

(1) angle 3is a right angle


Given

(2) the measure of angle 3 equals 90 degrees


Definition of right angle

(3) angle 1 plus angle 2 plus angle 3 forms a straight angle


Definition of straight angle

(4) the measure of angle 1 plus the measure of angle 2 plus the measure of angle 3 equals 180 degrees


Straight angles measure

(5) the measure of angle 1 plus the measure of angle 2 plus 90 degrees equals 180 degrees


?

(6) the measure of angle 1 plus the measure of angle 2 equals 90 degrees




(7) angle 1 and ang