Given that a of B is two thirds and a is not equal to 2, find the value of A-B + 1 of a + B-5

Given that a of B is two thirds and a is not equal to 2, find the value of A-B + 1 of a + B-5

∵a/b=2/3
∴a=2b/3
(a-b+1)/(a+b-5)
=(2b/3-b+1)/(2b/3+b-5)
=-(b-3)/5(b-3)
=-1/5.