Question

Solve each of the following systems of equations by the method of cross-multiplication :

$$\begin{gathered} \frac{57}{x+y}+\frac{6}{x-y}=5 \\ \frac{38}{x+y}+\frac{21}{x-y}=9 \end{gathered}$$

Answer 1

GIVEN:

To find: The solution of the systems of equation by the method of cross-multiplication:

Here we have the pair of simultaneous equation

Now rewriting the given equation as

By cross multiplication method we get

Consider the following for u

Consider the following for v

We know that

Now adding eq. (3) and (4) we get

And after substituting the value of x in eq. (4) we get

Hence we get the value of and