To solve the system below by eliminating the $y$ variable, what is the best first step? $ \begin{cases} 4x - 3y = 8 \\ 2x + 9y = 10 \end{cases} $

Multiply the first equation by 3.

Multiply the second equation by 3.

Add the equations together as they are.

Multiply the first equation by -3.

Which set of operations will prepare the system below for eliminating the $x$ variable? $ \begin{cases} 5x + 2y = 7 \\ 3x + 5y = 1 \end{cases} $

Multiply the first equation by 3 and the second by -5.

Multiply the first equation by 5 and the second by 3.

Multiply the first equation by 2 and the second by 5.

Multiply the first equation by 3 and the second by 5.