A variable $y$ is directly proportional to $x$. If the graph of this relationship passes through the point $(5, 2)$, what is the value of $y$ when $x = 1$?

True or False: The formula $\frac{V}{R + r}$ can be correctly rewritten as $\frac{V}{R} + \frac{V}{r}$ by distributing the division across the addition in the denominator.

True or False: In pure algebra, to make $x$ the subject of the formula $y = (x - h)^2$, the result must be written as to account for both possible roots.

The kinetic energy $E$ of an object is directly proportional to the square of its velocity $v$. If an object's velocity is reduced by $50\%$, by what percentage does its kinetic energy decrease?

To make $x$ the subject of the formula $y = 3(x - 4)^2 + 5$, what is the correct first step in the 'undoing' process?