Answer:
Put 4 in the place of x then you'll get

X+6 = 3x - 12 (right?)
6 = 2x-12
18 = 2x
9 = x
4x-15 = 2x+3
2x-15 = 3
2x = 18
x = 9
Basically, x = 9
Answer:
12 cm
Step-by-step explanation: i think if its not im sorry
hope it helps you , you can tell me in the comment box
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