Question

How do you FOIL `(x+4)(x+1)`?

Answer 1

Given `color(red)((x+4))color(blue)((x+1))`

F irst terms: `color(red)(x)xxcolor(blue)(x) = x^2`
O utside terms: `color(red)(x)xxcolor(blue)(1) = 1x`
I nside terms: `color(red)(4)xxcolor(red)(x) = 4x`
L ast terms: `color(red)(4)xxcolor(red)(1) = 4`

Sum of FOIL `=x^2+5x+4`