Since both angles are complementary, then Angle 1 + Angle 2 = 90°
Using algebra,
let Angle 2 be X and Angle 1 be (2X + 21°)
Now we have an equation of,
( 2X + 21 ) + X = 90°
step 1 : open up the brackets first.
step 2 : bring 21° to the other side (rmb to flip the sign)
step 3 : bring the 3 over n it becomes " ÷3 "
( 2X + 21° ) + X = 90°
2X + 21° + X = 90°
3X = 90° - 21°
X = ( 90° - 21° ) ÷ 3
= 23°
Sub X=23° into Angle 1 ( 2X + 21° ),
2(23°) + 21° = 67°
Therefore,
Angle 1 = 67°
i hope my solution helps :))
