I don't know exactly what needs to be answered, but I have till the end of the day to get most of this done, so please help-
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TEF = EGF + EFG
12x - 2 = ( 8x + 17 ) + ( 25 )
12x - 2 = 8x + 17 + 25
12x - 2 = 8x + 42
Add both sides 2
12x - 2 + 2 = 8x + 42 + 2
12x = 8x + 44
Subtract both sides by 8x
12x - 8x = 8x - 8x + 44
4x = 44
Divide both sides by 4
4x ÷ 4 = 44 ÷ 4
x = 11