If x+y = - 1, and xy = - 12, what is the value of (x+3) (y+3) ?

Here are my hints. You can solve it yourself

1 / xy = - 12 - -> x = - 12/y

2 / (-12/y) + y = - 1 - -> - (12/y) + (y²/y) = - 1 - -> - 12 + y² = - y - -> y²+y-12=0

3 / From y²+y-12=0 we can find y then use y to find x and then do your

(x+3) * (y+3)