Question

Point (3,-1) and (6,1) lie on the line represented by the equation px+qy=9, find the values of p and q

Answer 1

px+qy=9
p(3)+q(-1) =9
3p -q=9. -. ( 1 )

px+qy=9
p(6) +q(1) =9
6p +q=9. -(2)

subtract equation (1) from (2)
(6p+q=9)-(3p-q=9)
=9p=9
p=9/9
p=1

6p+q=9
6(1)+q=9
6+q=9
q=9-6
q=3

Answer 2

Equation of line is px +qy = 9

Since (3,-1) lies on the line:

3p-q =9

Also (6,1) lies on the line:

6p+q =9

Solving these two equation simultaneously or by subsitution method

We get p= 2 and q = -3.