Question

If px^2+3x+q=0 has two roots X= -1 and X=-2, find p-q.

Answer 1

if x=-1
p-3+q=0
p+q=3-------eq(1)
if x=-2
4p-6+q=0
4p+q=6----------eq(2)
on solving eq1 and eq2

p=1
substitute p=1 in eq(1)
1+q=3
q=2
p-q=1-2=-1
p-q=-1 is the answer