We know that a line passes through 3 points $$(-10,-18),(20,22) \&(x, 2)$$.

The slope of a line joining points $$\left(x_1, x_2\right) \&\left(y_1, y_2\right)$ is $\frac{y_2-y_1}{x_2-x_1}$$

Now, the slope of the line found using any two of the three points say $$(-10,-18) \&(20,22)$$ above must be same as that found using the some other pair of two of the three points, say $$(20,22) \&(x$$, 2) so we get $$\frac{22-(-18)}{20-(-10)}=\frac{2-22}{x-20}$$ i.e. $$\frac{40}{30}=\frac{-20}{x-20} \Rightarrow x=5$$

Hence the answer is C.