Respuesta :

distributive property...
-7 + 4x = 9
move the 7 over
4x = 16
x = 4
-(7 - 4x) = 9

Distribute the negative and the equation becomes:
-7 + 4x = 9

Add 7 to both sides and the equation becomes:
4x = 16

Divide both sides by 4
X = 4