The value of   $$ {(0.03)^2 - (0.01)^2}\over 0.03-0.01 $$

$$3\sqrt{ {72.9\over0.4096}}$$ is equal to : 

Find the value of given expression.

3 – (– 6) {– 2 – 9 – 3} ÷ 7{1 + (– 2) (– 1)}

If 3x + 7y=75, 5x- 5y= 25, then the value of (x +y)=?

If 12x – 15 y =9x + 5y, the value of $$ {x^{2}+{y^{2}}\over{x^{2}-y^{2}}}$$ is

The value of $${\sqrt{40+\sqrt{9\sqrt{81}}} }$$ is

The simplified value of
$${{1\over 3}÷{1\over 3}×{1\over 3}\over{1\over 3}÷{1\over 3}of{1\over 3}}-{1\over 9}$$

What is the value of x ?