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What are the zeros of f(x) = x2 + x - 30?

O A. x= -6 and x = 5
B. x= -2 and x= 15
o
C. x= -5 and x = 6
D. x= -15 and x = 2
SS

User Totally
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2 Answers

2 votes

Hey there! :)

Answer:

A. x = -6 and x = 5.

Explanation:

Given:

f(x) = x² + x - 30

Factor the equation by finding two numbers that sum up to 1 and multiply into -30. We get:

-5, 6

Use these to express this quadratic function in factored form:

f(x) = (x - 5) (x + 6)

Set each factor equal to 0 to solve for the zeros of the equation:

0 = x - 5

x = 5

-------------

0 = x + 6

x = -6

Therefore, the correct answer is A. x = -6 and x = 5.

3 votes

Answer:

A

Explanation:

The zeroes of the function are the x values when f(x) = 0 so we can write:

0 = x² + x - 30

0 = (x + 6)(x - 5) (To factor this we need to find 2 numbers that have a sum of 1 and a product of -30; these numbers are 6 and -5)

x + 6 = 0 or x - 5 = 0 (Use Zero Product Property)

x = -6, 5

User Carlos Cordoba
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