Answer
given,
2 p+ q - r = 8 ...................(1)
q + r = 4......................(2)
p - q = 2...................(3)
solving equation (1) and (2)
2p + 2 q = 12
p + q = 6..............(4)
now, solving equation 3 and 4
2 p = 8
p = 4
putting value of p in equation (4)
q = 6 -4
q = 2
putting value in equation (2)
2 + r = 4
r = 2
