(b-7)(b+5)=(b+8)(b+9)

Solution for (b-7)(b+5)=(b+8)(b+9) equation:

(b-7)(b+5)=(b+8)(b+9)

We move all terms to the left:

(b-7)(b+5)-((b+8)(b+9))=0

We multiply parentheses ..

(+b^2+5b-7b-35)-((b+8)(b+9))=0


We calculate terms in parentheses: -((b+8)(b+9)), so:

(b+8)(b+9)

We multiply parentheses ..

(+b^2+9b+8b+72)

We get rid of parentheses

b^2+9b+8b+72

We add all the numbers together, and all the variables

b^2+17b+72

Back to the equation:

-(b^2+17b+72)


We get rid of parentheses

b^2-b^2+5b-7b-17b-35-72=0

We add all the numbers together, and all the variables

-19b-107=0

We move all terms containing b to the left, all other terms to the right

-19b=107

b=107/-19

b=-5+12/19