Question

Could you please help me on this

Answer 1

-x^2 +10x + 7

`-x^2 +10x + 7`

Explanation:

its the gray shaded area [(x+1)*(x+7)] minus the white area [(x-1)*(2x)]

AKA: [(x+1)*(x+7)] - [(x-1)*(2x)]

so first you foil to get both areas

gray region: (x+1)*(x+7) = x^2 + 8x + 7

white region: (x-1)*(2x) = 2x^2 - 2x

and then you subtract the white from the gray

`(x^2 + 8x + 7) - (2x^2 - 2x)`

-x^2 +10x + 7