Question

How do you multiply `(4x+5) (x+1)`?

Answer 1

Use FOIL -- First, Outer, Inner, Last -- and add the results

Explanation:

F:
`4x*x=4x^2`
O:
`4x*1=4x`
I:
`5*x=5x`
L:
`5*1=5`

Now add:
`4x^2+4x+5x+5=4x^2+9x+5`