Answer:
The answer is: x = 18.
Step-by-step explanation:
1) That is a right angle, so it equals 90 degrees. You can add together the 'x'es that you see in the photo, and x + x +3x = 5x.
2) Set that equal to 90, so: 5x = 90.
3) Divide by 5 on both sides, to get x = 18.
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