Question

How do you combine like terms for `3x^2 + 21x + 5x + 10x^2`?

Answer 1

See a solution process below:

Explanation:

First, group like terms;

`3color(red)(x^2) + 10color(red)(x^2) + 21color(blue)(x) + 5color(blue)(x)`

Now, combine the coefficients of the like terms:

`(3 + 10)color(red)(x^2) + (21 + 5)color(blue)(x)`

`13color(red)(x^2) + 26color(blue)(x)`

Answer 2

Looks like you've already splitted the middle term

Explanation:

But splitting isn't what we need here.... add them up
`13x^2+26x`
Notice that both have `13x` as common...
Factorize
`13x(x+2)`