How do you factor $-5x^2 - x + 4$ ?

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Answer 1 · 2017-03-29T21:31:00

$(-5x-4)(x+1)$

First, you would find the zeros by applying the quadratic formula:

$x=(1+-sqrt(1-4(-5)4))/(2(-5))$

$x=(1+-9)/-10$

$x_1=(1-9)/-10=-8/-10=4/5$

$x_2=(1+9)/-10=-1$

Then you could apply the formula and factor:

$ax^2+bx+c=a(x-x_1)(x-x_2)$

$-5x^2-x+4=-5(x-4/5)(x+1)$

$=(-5x-4)(x+1)$

How do you factor -5x^2 - x + 4-5x^2 - x + 4?