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

Aug 25, 2015

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 = $18 x \cdot \left(- 12 x\right) = - 216 {x}^{2}$
Product of OUTSIDE terms = $18 x \cdot \left(- 6\right) = - 108 x$
Product of INSIDE terms = $20 \cdot \left(- 12 x\right) = - 240 x$
Product of LAST terms = $20 \cdot \left(- 6\right) = - 120$

SUM = $- 216 {x}^{2} + \left(- 108 x\right) + \left(- 240 x\right) + \left(- 120\right)$

$= - \left(216 {x}^{2} + 108 x + 240 x + 120\right)$

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