Question

solve the following system of simultaneous linear equation by the elimination method px + qy = p - q and qx - py = p + q

Answer 1

px + qy = p-q ...............(i ) ×q
qx + py = p + q .............(ii) ×p

pqx +q^2y=pq-q^2
pqx-p^2y=p^2+pq
- + - -
________________
(p^2+q^2)y = - (p^2+q^2)
y =– 1
put the value of y in equ (i )

px - q =p-q
px = p-q+q
px =p
x=1

x=1 and y= -1