The "slide and divide" method is a way to factor second degree poynomials of the form ax2 + bx + c, and is designed for the "hard" case, when the a value of the second degree polynomial is not 1.
This method will be illustrated by using an example. Suppose we want to factor 3x2 + x - 10.
1) "Slide" the a value (3) to the end by multiplying it by c (-10). We get: x2 + x - 30.
2) We have created the "easy" version, where a = 1. Factor using reverse FOIL (or your favorite method). We get:
(x - 5)(x + 6)
3) Now divide the number parts of these binomials by the value a (3):
(x + 6/3)(x - 5/3)
4) Reduce.
(x + 2)(x - 5/3)
5) If we still have a fraction in either of the binomials, move the denominator from the bottom of the fraction to the coefficient of the variable:
(x + 2)(3x - 5)
6) Check by multiplying back to see if it matches our original polynomial:
(x + 2)(3x - 5) = 3x2 + x - 10
We have our original polynomial, so we have found the correct factors.
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