If r=9, b=5, and g=6. what does (r+b-g) (b-g) equal?

(r+b-g) (b-g)

I this question, we have the values of r, b and g given, which are r=9, b=5, g=6

And we have to find the value of the given expression. And for that we need to substitute the values of r, b and 9 in the expression. That is,

(9+5-6) (5-6) = 8 (-1) = - 8

So the value of the given expression is - 8.