Respuesta :

I feel like i answered this before but it is:

a-9
3
A minus 9 all over 3
solve for b.

a=3b+9

Flip the equation.

3b+9=a

Add -9 to both sides.

3b+9+−9=a+−9

3b=a−9

Divide both sides by 3.

3b/3=a−9/3

b=1/3a−3