Question

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

3x + 2y + 25 = 0;

2x + y + 10 = 0

Answer 1

The given system of equations is 

3x + 2y + 25 = 0

2x + y + 10 = 0 

For cross multiplication we use,

Comparing the above two equations with the general form, we get

Hence, the solution for the given system of equations is x = 5 and y = -20.