if m ∟n, solve for x. (x + 21) (3x + 9) giving brainliest
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Answer:
x=15
Step-by-step explanation:
Add the two equations together because there is a 90 degree angle. You can add the two to get :
4x+30=90
-30 from both sides
4x=60
Divide by 4 on both sides to get your answer!
x=15