How do you simplify #(4x+3)(4x-7)#?

1 Answer
May 12, 2018

#16x^2 - 16x - 21#

Explanation:

To solve this, we can use foil:
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As you can see, the first thing to do is multiply the #color(red)("firsts")#:
#color(red)(4x * 4x = 16x^2)#

Next the #color(purple)("outsides")#:
#color(purple)(4x * -7 = -28x)#

Now the #color(darkturquoise)("insides")#:
#color(turquoise)(3 * 4x = 12x)#

And finally the #color(limegreen)("lasts")#:
#color(limegreen)(3 * -7 = -21)#

Combine them all together we get:
#16x^2 - 28x + 12x - 21#

We can still combine like terms: #-28x + 12x = -16x#

So, finally, the answer is:
#16x^2 - 16x - 21#

Hope this helps!