Hey there!
7h - 15h + 40 = -72
COMBINE the LIKE TERMS
-8h + 40 = -72
SUBTRACT 40 to BOTH SIDES
-8h + 40 - 40 = -72 - 40
CANCEL out: 40 - 40 because it gives you 0
KEEP: -72 - 40 because it helps solve for the h-value
NEW EQUATION: -8h = -72 - 40
SIMPLIFY IT!
-8h = -112
DIVIDE -8 to BOTH SIDES
-8h/-8 = -112/-8
CANCEL out: -8/-8 because it gives you 1
KEEP: -112/-8 because it helps solve for the h-value (it gives you the result of it!)
NEW EQUATION: h = -112/-8
SIMPLIFY IT!
h = 14
Therefore, your answer is: h = 14
Good luck on your assignment and enjoy your day!
~Amphitrite1040:)