3(gameMachines) + 5(6) = 72lbs
3(gameMachines) = 42
gameMachine = 14
I think you're having trouble because the equation you wrote for 8a has a slight typo.
The question says that the length is 9 less than twice the width. Your equation states the length is 9 times the width minus 2. So the length actually equals 2w – 9, meaning that w(2w – 9) = 180
Hope this helps! If you're still having trouble, let me know :)
f(x) = 20x² - 18x - 25
f(-1) = 20(-1)² - 18(-1) - 25
= 20 + 18 - 25
= 13
