Question

How do you foil `2 (x+2) (x+5)`?

Answer 1

FOIL can only be applied to the 2 binomials; the result of that multiplication can then be multiplied by `2` to get:
`color(white)("XXXX")` `2x^2+14x+20`

Explanation:

Evaluating the product of two binomials using FOIL:

Sum
`color(white)("XXXX")`product of First terms
`color(white)("XXXX")`product of Outside terms
`color(white)("XXXX")`product of Inside terms
`color(white)("XXXX")`product of Last terms

For the given example: `2(x+2)(x+5)`:

We can apply FOIL to `(x+2)(x+5)` as
`color(white)("XXXX")`First terms: `x, x` `color(white)("XXXX")`Product `= x^2`
`color(white)("XXXX")`Outside terms: `x, +5` `color(white)("XXXX")`Product `= +5x`
`color(white)("XXXX")`Inside terms: `+2, x` `color(white)("XXXX")`Product `= +2x`
`color(white)("XXXX")`Last terms: `+2, +5` `color(white)("XXXX")`Product `= +10`

Sum
`color(white)("XXXX")` `= x^2+5x+2x+10`

`color(white)("XXXX")` `= x^2+7x+10`

So
`color(white)("XXXX")` `(x+2)(x+5) = x^2+7x+10`

and
`color(white)("XXXX")` `2(x+2)(x+7) = 2x^2+14x+20`