Answer:
x=15
Step-by-step explanation:
Well, you have 2 numbers that sum up to 90 (the angle) so you can first minus the one you know, making your number from 90-30=60. Now all thats left is the 4x=60, which you can do 60/4=15 to get your answer that x=15.
x = 15
The sum of 30 and 4x = 90, that is
4x + 30 = 90 ← equation to solve
Subtract 30 from both sides
4x = 60 ( divide both sides by 4 )
