The answer is u = 8.
Distribute 5 into (u +8): 5u + 40
You now have the following:
5u + 40 - 7u = 24.
Next, combine like terms by adding 5u and -7u, which will give you -2u.
-2u + 40 = 24
Next, to isolate 2u, you must subtract 40 from both sides of the equation:
-2u + 40 -40 = 24 - 40
-2u = -16
Next, simplify by dividing both sides of the equation by -2 to solve for u:
-2u/-2 = -16/-2
u = 8.