Hey there!
5x - 7 = y
5x - 7 = 8
ADD 7 to BOTH SIDES
5x - 7 + 7 = 8 + 7
CANCEL out: -7 + 7 because it give you 0
KEEP: 8 + 7 because it help solve for the x-value
NEW EQUATION: 5x = 8 + 7
SIMPLIFY IT!
5x = 15
DIVIDE 5 to BOTH SIDES
5x/5 = 15/5
CANCEL out: 5/5 because it give you 1
KEEPs 15/5 because it give you the x-value
NEW EQUATION: x = 15/5
SIMPLIFY IT!
x = 3
Therefore, your answer is: x = 3
Good luck on your assignment & enjoy your day!
~Amphitrite1040:)