How do you factor $7x^2 - 9x + 2$ ?

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Answer 1 · 2015-06-06T16:54:48

You find its roots and turn them into factors by equaling them to zero.

Let's find the roots using Bhaskara:

$(9+-sqrt(81-4(7)(2)))/14$

$(9+-sqrt(81-56))/14$

$(9+-sqrt25)/14$

$(9+-5)/14$

$x_1=1$ , which, equaled to zero is $x-1=0$
$x_2=2/7$ , which, equaled to zero is $7x-2=0$

Thus, we can factor $7x^2-9x+2$ this way:

$(x-1)(7x-2)$

Answer 2 · 2015-06-06T21:56:32

$f(x) = 7x^2 - 9x + 2.$

Since (a + b + c) = 0, one factor is (x - 1) and the other is $(-c/a = -2/7)$

f(x) = (x - 1)(7x - 2)

How do you factor 7x^2 - 9x + 27x^2 - 9x + 2?