Question

Are `(3c+7)` and `(7c+3`) the binomial factors of `21c^2+58c+21`?

Answer 1

Yes they are.

`=(3c+7)(7c+3)`

Explanation:

`21c^2+58c+21`

`=21c^2+49c+9c+21`

`=7c(3c+7)+3(3c+7)`

`=(3c+7)(7c+3)`