Question

Which of the following polynomials has -3 as a zero?

A.
x^2 + 3


B.
(x – 3)


C.
x^2 – 9


D.
x^2 – 3x

Answer 1

Hi Rehan......

If any of these polynomial has - 3 as it's zero , then when we substitute - 3 in the place of x , we will get zero....

in option A

x² + 3

= ( - 3 )² + 3 = 9 + 3 = 6 ≠ 0 .... so option A is not

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In option B

x - 3 = - 3 - 3 = - 6 ≠ 0 .... so option B is not

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In option C

x² - 9 = (-3)² - 9 = 9 - 9 = 0 ...so option C is a polynomial which has - 3 as a zero..

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In option D

x² - 3x = 9 + 9 = 18 ≠ 0..... so option D is not

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So your answer is Option C....


hope it helps

Answer 2

hello...

Question :- Which of the following polynomials has -3 as a zero?

A.
x^2 + 3
B.
(x – 3)
C.
x^2 – 9(✔️)
D.
x^2 – 3x

EXPLANATION

(A) P(x) = x² + 3

p(-3) = (-3)² + 3

p(-3) = 9 + 3

= 12 ≠ 0
Hence option A is not the correct option.

(B) p(x) = (x – 3)

p(-3) = ( - 3 - 3 )

p(-3) = -6

-6 ≠ 0
Hence option B is not the correct option.

(C) p(x) = x^2 – 9

p(-3) = (-3)² - 9

p(-3) = 9-9

0 = 0
Hence option C is correct option

(D) p(x) = x^2 – 3x

p(-3) = (-3)² - 3(-3)

p(-3) = 9 - 6

3 ≠ 0
Hence option D is not correct option