Note: I'm afraid I can't put the work for the answers, for lack of time =/
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1. 0 or -3
2. 0 or 4
3. -2 or 3
4. 0 or 1/2
5. -2 or 3
6. 0 or 5
7. 0 or 7
8. 0 or -2
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9. Substitute 0 for h in "h = -16x^2 + 16x" then solve for x
0 = -16x^2 + 16x
Subtract -16x^2+16x from both sides.
0−(−16x2+16x)=−16x2+16x−(−16x2+16x)
16x2−16x=0
Factor the left side of the equation
16x(x−1)=0
Set factors to equal 0
16x=0 or x−1=0
x = 0 or x = 1