Implicit differentiation
chain rule is important here
I'll show the steps partially




now evaluate for (-2,2)
x=-2 and y=2



that's it, simplest form
Answer:
The answer would be (16 , ∞)
Step-by-step explanation:
X-9=12
x-9+9=12+9
You need to add 9 to each side of the equation.
x=21
Answer:
20x
Step-by-step explanation:

By the way this problem is worded, he spends 75 minutes reading and cleaning, but there seems to be not enough information because the way it is worded, it means he has 75 minutes until he needs to GET READY, not play in the actual game. (40 + 35 = 75).