Question

Can someone help please? Easy math for others but I just can’t understand! Pic included!

Answer 1

Answer:  Choice A) -16, 0, 0, 144

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Work Shown:

plug in x = 1

y = x^2 - 8x - 9

y = (1)^2 - 8(1) - 9

y = 1 - 8(1) - 9

y = 1 - 8 - 9

y = -16

So x = 1 pairs up with y = -16

We can stop here since choice A is the only one that has -16.

So choice A must be the answer.

For the sake of completeness, let's plug in the other x values.

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plug in x = -1

y = x^2 - 8x - 9

y = (-1)^2 - 8(-1) - 9

y = 1 - 8(-1) - 9

y = 1 + 8 - 9

y = 0

x = -1 pairs up with y = 0

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plug in x = 9

y = x^2 - 8x - 9

y = (9)^2 - 8(9) - 9

y = 81 - 8(9) - 9

y = 81 - 72 - 9

y = 0

x = 9 pairs up with y = 0

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plug in x = -9

y = x^2 - 8x - 9

y = (-9)^2 - 8(-9) - 9

y = 81 - 8(-9) - 9

y = 81 + 72 - 9

y = 144

x = -9 pairs up with y = 144

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When you plug in x = 1, -1, 9 and -9, then the y values are y = -16, 0, 0 and 144 in that exact order.