Question

How do you foil `(18x + 20)(–12x – 6)`?

Answer 1

`color(blue)((18x+20)(–12x–6) = -(216x^2 + 348x + 120)`

Explanation:

FOIL stands for:

Product of FIRST terms +
Product of OUTSIDE terms +
Product of INSIDE terms+
Product of LAST terms

Applying this concept to the expression `color(blue)((18x+20)(–12x–6)`, we get:

Product of FIRST terms = `18x*(-12x) = -216x^2`
Product of OUTSIDE terms = `18x*(-6) = -108x`
Product of INSIDE terms = `20*(-12x) = -240x`
Product of LAST terms = `20*(-6) = -120`

SUM = `-216x^2 + (-108x) + (-240x) + (-120)`

`= -(216x^2 + 108x + 240x + 120)`

`= color(blue)(-(216x^2 + 348x + 120)`