How do you factor $-2x^2 + 1x + 1$ ?

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Answer 1 · 2015-11-07T18:09:30

Start by setting the expression equal to zero, then use the ABC-formula.

The ABC-formula is:
$(-b+-sqrt(b^2 - 4ac))/(2a)$

Insert the values for a, b and c (which are the coefficients(red) in your expression: $color(red)(-2)x^2 + color(red)(1)x + color(red)(1)$

$x =(-1 +- sqrt(1^2 - 4 * (-2) * 1)) / (2*(-2)) to (-1 +- sqrt(1+8)) / (-4) to (-1+-3)/-4$

$x_1 = (-1 + 3)/-4= 2/-4 = -1/2$

$x_2 = (-1 - 3)/-4= (-4) /(-4) = 1$

Put these values into $(x-x_1)(x-x_2)$

$(x-(-1/2))(x-1)$
$(x+1/2)(x-1)$

How do you factor -2x^2 + 1x + 1-2x^2 + 1x + 1?