help me out thank you so much whoever does!!

Answer:
b=45
Step-by-step explanation:
The two angles form a right angle. This is shown through the box drawn at the angle's vertex; this represents that it is a right angle. A right angle is equal to 90 degrees b can be found by using the other angle. Since 45 and b are complementary angles 45+b=90. This means that b must equal 45 degrees.