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2 years ago

Help with #9 please?

Mathematics

1 answer:

nekit [7.7K]2 years ago

4 0

We're given a parabola

$y=x^2-4$

and a line

$y = 2x+b$

The zeros of the parabola are

$0=x^2-4$

$4=x^2$

$x=\pm 2$

We see that (-2,0) is on the line as well:

$y = 2x+b$

$0 = 2(-2)+b$

$b=4$

Choice D

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