To solve for  we must move all of the numbers to the other side of the equation as .

To do this in a problem where  is being divided by a constant, we must multiply both sides of the equation by that constant.

In this case the constant is $\displaystyle 4$, so we multiply each side of the equation by $\displaystyle 4$ to make it look like this: $\displaystyle (4)\frac{x}{4}=(15)(4)$

The $\displaystyle 4$s on the left cancel to give us $\displaystyle x=(15)(4)$.

Multiply to find $\displaystyle x=60$.

To solve for  we must get all of the constants on the other side of the equation as .

To do this in a problem where a number is being added to , we must subtract the number from both sides of the equation.

In this case the number is $\displaystyle 64$, so we subtract $\displaystyle 64$ from each side of the equation: $\displaystyle x+64-64=91-64$

The $\displaystyle 64$s on the left side cancel: $\displaystyle x=91-64$

Then we perform the necessary subtraction to get the answer, $\displaystyle x=27$.

To solve this one-step algebraic equation, we use opposite operations. The variable $\displaystyle x$ in this equation is being multiplied by 4. The opposite operation to multiplication is division; therefore, we divide both sides of the equation by 4:

$\displaystyle 4x = 20$

$\displaystyle \frac{4x}{4} = \frac{20}{4}$

$\displaystyle x = 5$

To solve this one-step algebraic equation, we use opposite operations. The variable $\displaystyle x$ in this equation is being divided by 5. The opposite operation to division is multiplication; therefore, we multiply both sides of the equation by 5:

$\displaystyle \frac{x}{5} = 10$

$\displaystyle 5\cdot \frac{x}{5} = 10\cdot 5$

$\displaystyle x = 50$

To solve this one-step algebraic equation, we use opposite operations. The variable $\displaystyle x$ in this equation is being subtracted by 7. The opposite operation to subtraction is addition; therefore, we add 7 to both sides of the equation.

$\displaystyle x-7=5$

$\displaystyle x-7+7=5+7$

$\displaystyle x=12$

To solve this one-step algebraic equation, we use opposite operations. The variable $\displaystyle x$ in this equation is being added to the number 7. The opposite operation to addition is subtraction; therefore, we subtract 7 from both sides of the equation.

$\displaystyle x+7=-3$

$\displaystyle x+7-7=-3-7$

$\displaystyle x = -10$

To solve this one-step algebraic equation, we use opposite operations. The variable $\displaystyle x$ in this equation is being multiplied by the number $\displaystyle -3$. The opposite operation to multiplication is division; therefore, we divide both sides of the equation by $\displaystyle -3$. 

$\displaystyle -3x = -18$

$\displaystyle \frac{-3x}{-3} =\frac{-18}{-3}$

$\displaystyle x=6$

To solve this one-step algebraic equation, we use opposite operations. The variable $\displaystyle x$ in this equation is being subtracted by the number 3. The opposite operation to subtraction is addition; therefore, we add 3 to both sides of the equation.

 $\displaystyle x-3=-4$

$\displaystyle x-3+3=-4+3$

$\displaystyle x=-1$

To solve this one-step algebraic equation, we use opposite operations. The variable $\displaystyle z$ in this equation is being multiplied by the number $\displaystyle -4$. The opposite operation to multiplication is division; therefore, we divide both sides of the equation by $\displaystyle -4$. 

$\displaystyle -4z=16$

$\displaystyle \frac{-4z}{-4}=\frac{16}{-4}$

$\displaystyle z = -4$

To solve this one-step algebraic equation, we use opposite operations. The variable $\displaystyle y$ in this equation is being divided by the number 3. The opposite operation to division is multiplication; therefore, we multiply both sides of the equation by 3.

$\displaystyle \frac{y}{3}=-1$

$\displaystyle 3\cdot \frac{y}{3}=-1\cdot 3$

$\displaystyle y=-3$