Answer:
x = 9
Step-by-step explanation:
angle <1 and angle <2 is complementary and their sum is 90 degrees
3x + 5x + 18 = 90 add like terms
8x + 18 = 90 subtract 18 from both sides
8x = 72 divide both sides by 8
x = 9 to find the measure of angle <1 replace x with the value we found
