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Factor and find the x-intercepts f(x) = x^2– 3x - 4

User Rieder
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1 Answer

5 votes

Answer:

see explanation

Explanation:

To find the x- intercepts let f(x) = 0, that is

x² - 3x - 4 = 0

Consider the factors of the constant term (- 4) which sum to give the coefficient of the x- term (- 3)

The factors are - 4 and + 1, since

- 4 × 1 = - 4 and - 4 + 1 = - 3, thus

(x - 4)(x + 1) = 0 ← in factored form

Equate each factor to zero and solve for x

x - 4 = 0 ⇒ x = 4

x + 1 = 0 ⇒ x = - 1

x- intercepts are (- 1, 0 ) and (4, 0 )

User Cody Harness
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