Question

How do you factor `y= 7x^3+28x^2` ?

Answer 1

Both `7x^3` and `28x^2` are divisible by `7x^2`, so:

`7x^3+28x^2 = 7x^2(x+4)`

Explanation:

`7x^3 = 7x^2*x`

`28x^2 = 7x^2*4`

So:

`7x^3+28x^2 = (7x^2*x)+(7x^2*4) = 7x^2*(x+4)`