Solve for x and y:
x + y = 5xy, 3x + 2y = 13xy (x ≠ 0, y ≠ 0)
We have
x + y = 5xy
and 3x + 2y = 13xy
where x≠0 and y≠0
Lets simplify these equations.
x + y = 5xy
Dividing the equation by xy throughout,
⇒
Assuming p = 1/y and q = 1/x, we get
p + q = 5 …(i)
Also, 3x + 2y = 13xy
Dividing the equation by xy throughout,
⇒
Assuming p = 1/y and q = 1/x, we get
⇒ 3p + 2q = 13 …(ii)
To solve these equations, we need to make one of the variables (in both the equations) have same coefficient.
Lets multiply eq.(i) by 2, so that variable q in both the equations have same coefficient.
Recalling equations (i) & (ii),
p + q = 5 [×2]
3p + 2q = 13
⇒ - p = - 3
⇒ p = 3
Substitute p = 3 in eq.(i)/eq.(ii), as per convenience of solving.
Thus, substituting in eq.(i), we get
3 + q = 5
⇒ q = 5 – 3
⇒ q = 2
Thus, p = 3 and q = 2
As q = 1/x,
⇒ 2 = 1/x
⇒ x = 1/2
And p = 1/y
⇒ 3 = 1/y
⇒ y = 1/3
Hence, we have x = 1/2 and y = 1/3