If $$\sqrt x+\frac{2}{5}×70=20×\frac{1}{4}×7$$​, then the value of $$x$$​ is:

Correct option is C

Given:

$$\sqrt x+\frac{2}{5}×70=20×\frac{1}{4}×7$$

Solution:

$$\sqrt x+\frac{2}{5}×70=20×\frac{1}{4}×7$$

$$\sqrt x+2×14=5×7$$

​​$$\sqrt x+28=35$$

​$$\sqrt x=35-28$$

$$\sqrt x=7$$

x = 49