Let $\displaystyle x$ be the number of hours Veronica must work.

Since we know that she is paid $\displaystyle \$120$ per hour, we can write the following equation:

$\displaystyle 120x=1920$

To solve for $\displaystyle x$, divide both sides by $\displaystyle 120$.

$\displaystyle 120x\div120=1920\div120$

$\displaystyle x=16$

Veronica needs to work for $\displaystyle 16$ hours to earn $\displaystyle \$1920$.

Let $\displaystyle x$ be the amount Jimmy had before buying groceries.

Since we know that he spent $\displaystyle \$45.10$ on groceries, we can write the following equation:

$\displaystyle x-45.10=3.66$

To solve for $\displaystyle x$, add $\displaystyle 45.10$ to both sides of the equation.

$\displaystyle x-45.10+45.10=3.66+45.10$

$\displaystyle x=48.76$

Jimmy had $\displaystyle \$48.76$ before buying groceries.

To solve for $\displaystyle x$, you will need to get $\displaystyle x$ on its own. To do so, divide both sides by $\displaystyle 3$.

$\displaystyle 3x=-9$ 

$\displaystyle \frac{3x}{3}=\frac{-9}{3}$

$\displaystyle x=-3$

To solve for $\displaystyle x$, you will need to get $\displaystyle x$ on its own. To do so, divide both sides by $\displaystyle 2$.

$\displaystyle 4x=\frac{1}{2}$ 

$\displaystyle 4x\div4=\frac{1}{2}\div4=\frac{1}{2}\times\frac{1}{4}$

$\displaystyle x=\frac{1}{8}$

To solve for $\displaystyle x$, you will need to get $\displaystyle x$ on its own. To do so, divide both sides by $\displaystyle -5$.

$\displaystyle -5x=\frac{1}{3}$ 

$\displaystyle -5x\div -5=\frac{1}{3}\div -5=\frac{1}{3}\times-\frac{1}{5}$

$\displaystyle x=-\frac{1}{15}$

Let $\displaystyle x$ be the number of hours Michael spends practicing.

We know from the question that Catherine spends $\displaystyle 4$ more hours practicing. We can then write the following expression to show the number of hours Catherine spends practicing in terms of $\displaystyle x$:

$\displaystyle x+4$

Since we also know that Catherine spent $\displaystyle 15$ hours practicing, we can then write the following equation:

$\displaystyle x+4=15$

To solve for $\displaystyle x$, subtract $\displaystyle 4$ from both sides.

$\displaystyle x+4-4=15-4$

$\displaystyle x=11$

Michael spent $\displaystyle 11$ hours practicing basketball.

In order to solve for $\displaystyle x$, subtract $\displaystyle 9$ from both sides of the equation.

$\displaystyle x+9=8$

$\displaystyle x+9-9=8-9$

$\displaystyle x=-1$

In order to solve for $\displaystyle y$, you will need to add $\displaystyle 6$ to both sides of the equation.

$\displaystyle y-6=9$

$\displaystyle y-6+6=9+6$

$\displaystyle y=15$

In order to solve for $\displaystyle y$, you will need to add $\displaystyle \frac{1}{2}$ to both sides of the equation.

$\displaystyle y-\frac{1}{2}=-2$

$\displaystyle y-\frac{1}{2}+\frac{1}{2}=-2+\frac{1}{2}$

$\displaystyle y=-\frac{4}{2}+\frac{1}{2}$

$\displaystyle y=-\frac{3}{2}$

In order to solve for $\displaystyle y$, add $\displaystyle 0.8$ to both sides of the equation.

$\displaystyle y-0.8=1$

$\displaystyle y-0.8+0.8=1+0.8$

$\displaystyle y=1.8$