Pair of Linear ...

The solution of $$\sqrt{2}x+\sqrt{3}y=0$$ and $$\sqrt{3}x+\sqrt{8}y=0$$ is

If $$7$$ pens and $$3$$ books cost $$Rs 1395$$, while $$5$$ pens and $$4$$ books cost $$Rs 1665$$. Find the cost of a  book

The sum of two numbers is $$2$$ and their difference is $$1$$. Find the numbers.

To eliminate x, from $$3x+y=7$$ and $$-x+2y=2$$ second equation is multiplied by ______

Solve:
$$4x + \frac{6}{y} = 15$$
$$6x - \frac{8}{y} = 14$$

 Solve for $$x$$ and $$y$$ by using method of substitution :
$$0.2x+0.3y=1.3$$; $$0.4x+0.5y=2.3$$

Solve 

Solve : $$ ax + by = a - b$$
             $$bx - ay = a + b$$

Solve $$0.2x+0.3y=1.3$$ 
$$0.4x+0.5y=2.3$$

Given two straight lines $$x + y - 7 = 0$$ and $$x - y + 3 = 0$$ . Find point of intersection of them.