Question

Find the value of x .....

Answer 1

we know that both angles combined make a 90 degree angle; to find x we set it up like this:
3x + 45 = 90
3x = 45
x = 15

Answer 2

x=15

Explanation:

It's right angle shown by orange color

If one side is 45, other side has to be 45 as well.

3x = 45

x = 45/3

x = 15