px + qy = r and 2px - qy = 2r when solving this system of equations, x =?

Solution:

Given system of equations px + qy = r and 2px - qy = 2r

Let px + qy = r --- eq[a]

Let 2px - qy = 2r --- eq[b]

In order to eliminate one variable, we need to add both the equations

By adding, +qy and -qy gets cancelled

px + qy = r
2px - qy = 2r
-------------
3px = 3r

⇒ px = r

⇒ x = r/p

px + qy = r and 2px - qy = 2r when solving this system of equations, x =?

Summary:

px + qy = r and 2px - qy = 2r when solving this system of equations, x = r/p.