Question

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

Answer 1

See a solution process below:

Explanation:

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`