Answer:
x should be 11
Step-by-step explanation:
What we know:
The angles shown are 13x + 12, and 2x + 3
The two angles are complementary, which means they equal 180 degrees.
(13x + 12) + (2x + 3) = 180
15x + 15 = 180
15x = 180 - 15
15x = 165
x = 11
