Question

How do you find the product of `(9x + 1) ( 7x - 10)` using the FOIL method?

Answer 1

`63x^2-83x-10`
(see below for application of FOIL)

Explanation:

FOIL `(9x+1)(7x-10)`

First terms of each binomial: `color(white)("x x")9x xx 7xcolor(white)("xxxx") = color(white)("xx")63 x^2`
Outside terms of each binomial: `9x xx(-10) = -90x`
Inside terms of each binomial: `color(white)("xx")1 xx 7xcolor(white)("xxx x") = color(white)("xxx")7x`
Last terms of each binomial: `color(white)("xx x")1 xx (-10) color(white)("x")= ul(-10color(white)("x"))`
`color(white)("XXXXXXXXXXXXXXXXXXXXXXXXXXXX")63x^2-83x-10`