Question

Using cross multiplication method, solve $3x+5y=25$
$7x+6y=30$

Answer 1

The given system of equations is $3x+5y-25=0$

$7x+6y-30=0$

Now, writing the coefficients for cross multiplication, we get

$\frac{x}{-150+150}=\frac{y}{-175+90}=\frac{1}{18-35}$. i.e., $\frac{x}{0}=\frac{y}{-85}=\frac{1}{-17}$.

Thus, we have x = 0, y = 5. Hence, the solution is (0, 5).