BRAINLIEST Help please I need this fast

Answer:
x=20
Step-by-step explanation:
Since this is a right angle, it is equal to 90 degrees
x + 3x+10 = 90
Combine like terms
4x+10 = 90
Subtract 10 from each side
4x+10-10 =90-10
4x=80
Divide by 4
4x/4=80/4
x = 20