If the equation A-3 (x + 5) = B (x + 2) of X is a linear equation of one variable, then B

If the equation A-3 (x + 5) = B (x + 2) of X is a linear equation of one variable, then B

a-3(x+5)=b(x+2)
a-3x-15=bx+2b
bx+3x=a-15-2b
(b+3)x=a-15-2b
Because equation A-3 (x + 5) = B (x + 2) is a linear equation with one variable
So B + 3 ≠ 0
b≠-3