How do you multiply $(4c+9d)^2$ ?

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Answer 1 · 2017-08-13T21:18:23

See a solution process below:

We can use this rule for multiplication to multiply the expression:

$(color(red)(x) + color(blue)(y))^2 = color(red)(x)^2 + 2color(red)(x)color(blue)(y) + color(blue)(y)^2$

Substituting $color(red)(4c)$ for $color(red)(x)$ and $color(blue)(9d)$ for $color(blue)(y)$ gives:

$(color(red)(4c) + color(blue)(9d))^2 => (color(red)(4c))^2 + (2 * color(red)(4c) * color(blue)(9d)) + (color(blue)(9d))^2 =>$

$16c^2 + 72cd + 81d^2$

How do you multiply (4c+9d)^2(4c+9d)^2?