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2 years ago

Which of the following is an x intercept of the function f(x)=x^2-81?

Mathematics

2 answers:

Anuta_ua [19.1K]2 years ago

7 0

Answer:

The correct option is C.

Step-by-step explanation:

The given function is

$f(x)=x^2-81$

Equate the given function equal to zero, to find the x-intercepts of the function.

$f(x)=0$

$x^2-81=0$

Add 81 both the sides.

$x^2=81$

Taking square root both the sides.

$x=\pm \sqrt{81}$

$x=\pm 9$

The x-intercepts of the given function are -9 and 9. Therefore the correct option is C.

Doss [256]2 years ago

4 0

x intercept when f(x) = 0
so
x^2-81 = 0
x^2 = 81
x = + 9 and x = -9

Answer
C -9

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2 years ago

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lianna [129]

Answer:

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Step-by-step explanation:

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Mean = np

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