jika p=q,tentukan b-2a =

2a + b = 5
b = 5 - 2a

a - b = -2
a - (5-2a) = -2
a - 5 + 2a = -2
3a = 3
a = 1

b = 5 - 2(1)
= 3

b - 2a = 3 - 2(1)
= 1