How do you foil #(16x + 13)(–8x + 15) #?

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Answer 1 · 2018-06-24T16:41:52

#-128x^2 + 136x + 195#

#(16x+13)(-8x+15)#

Use the distributive method FOIL (shown below) to simplify the expression:
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Following this image, we can multiply it out.

The #color(teal)("firsts")#:
#color(teal)(16x * -8x) = -128x^2#

The #color(indigo)("outers")#:
#color(indigo)(16x * 15) = 240x#

The #color(peru)"inners"#:
#color(peru)(13 * -8x) = -104x#

The #color(olivedrab)"lasts"#:
#color(olivedrab)(13 * 15) = 195#

Combine them all together to get:
#-128x^2 + 240x - 104x + 195#

We can still combine the like terms #color(blue)(240x)# and #color(blue)(-104x)#:
#-128x^2 + 136x + 195#

Hope this helps!