Question

How do you factor completely: `5x^2 + 20x`?

Answer 1

`5x(x+4)`

Explanation:

The first thing you should always do whilst factoring is find a common factor. In this case, it would be 5x as it divides into both of these.
Then take each variable and divide it by your factor.
`(5x^2) / (5x) = x`

`(20x)/(5x) = 4`

Then just put your factor on the outside of your bracket and the two other variables inside and you've got your answer!
`5x`(Your factor) `(x+4)` (The two other variables)
`5x(x+4)`