Hey there!
3x + 7 = 7x + 8 - 3x
3x + 7 = 4x + 8
SUBTRACT 4x to BOTH SIDES
3x + 7 - 4x = 4x + 8 - 4x
WORK IT OUT!
NEW EQUATION: -x + 7 = 8
-1x + 7 = 8
SUBTRACT 7 to BOTH SIDES
-1x + 7 - 7 = 8 - 7
CANCEL out: 7 - 7 because it give you 0
KEEP: 8 - 7 because it give you the value of x.
NEW EQUATION: -1x = 8 - 7
SIMPLIFY IT!
-1x = 1
DIVIDE -1 to BOTH SIDES
-1x/-1 = 1/-1
CANCEL out: -1/-1 because it give you 1
KEEP: 1/-1 because it give you the value of x
NEW EQUATION: x = 1/-1
SIMPLIFY IT!
x = -1
Therefore, your answer is: x = -1
Good luck on your assignment and enjoy your day!
~Amphitrite1040:)