Question 19232
Try this:
{{{x = ks^2/t}}} Multipy s by 2.
{{{x = k(2s)^2/t}}} = {{{4(ks^2)/t = 4x}}}  So, x is quadrupled when s is doubled.

{{{x = ks^2/t}}} Multiply s and t by 2.
{{{x = k(2s)^2/2t}}}
{{{x = 4ks^2/2t}}} = {{{2ks^2/t = 2x}}} So, x is doubled when both s and t are doubled.