Pre-Algebra - Math

The goal is to get alone on one side. Therefore you subtract from both sides to get . Then divide both sides by to get alone.

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Subtract from both sides of the equation, and simplify.

Divide both sides by . Be careful of the negative sign.

The sales tax is

The total grocery bill is .

The change is .

To isolate on one side, subtract seven from both sides

To solve the equation for , you must isolate on one side. Here you can divide both sides by 3.

To solve equations, you must perform the same operations on both sides.

Subtract 5 from both sides.

Remembering the final goal is to get the alone on one side of the equation.

To get rid of the , we perform the opposite operation. We add to each side of the equation, cancelling out the on the left side.

This brings the equation to .

If you put in for . Therefore it becomes .

Finally,

First you multiply the coefficients .

Then you multiply According to the laws of exponents, when you multiply two numbers with similar bases (both in this case) then you simply add the exponents .

Therefore, the final answer is .

In order to solve a one step equation, we want to isolate the variable. To do this, we pay special attention to what is being done to the variable. In this case we are multiplying the variable by . To "undo" this, we use the inverse of multiplication, which is division; thus we divide by on both sides. Note that we are dividing by since that is what is being multiplied; don't be tricked into dividing by .

Dividing both sides by , we get .

To solve for we must get all of the numbers 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 so we subtract from each side of the equation to make it look like this

The 's on the left side cancel to get

Then we perform the necessary subtraction to get the answer of .

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

To do this in a problem where is being multiplied by a number, we must divide both sides of the equation by the number.

In this case the number is so we divide each side of the equation by to make it look like this .

The s cancel to leave by itself.

Then we perform the necessary division to get the answer of .

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

To do this in a problem where is being subtracted by a number, we must add the number to both sides of the equation.

In this case the number is so we add to each side of the equation to make it look like this

The s cancel on the left side and leave by itself.

Then we perform the necessary addition to get the answer of .

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

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

In this case the number is so we multiply each side of the equation by to make it look like this

The 's on the left side cancel so we only have .

Then we perform the necessary multiplication to get the answer of .

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

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

In this case the number is so we multiply each side of the equation by to make it look like this

The 's on the left side cancel so we only have .

Then we perform the necessary multiplication to get the answer of

To solve for we must get all of the numbers 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 so we subtract from each side of the equation to make it look like this

The 's on the left side cancel to get

Then we perform the necessary subtraction to get the answer of .

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

To do this in a problem where is being multiplied by a number, we must divide both sides of the equation by the number.

In this case the number is so we divide each side of the equation by to make it look like this

The 's cancel to leave by itself.

Then we perform the necessary division to get the answer of .

To solve, you want to isolate the on one side.

To get ride of the , you add to both sides.

Then you divide by on both sides.

To solve for we must get all of the numbers 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 so we subtract from each side of the equation to make it look like this

The 's on the left side cancel to get

Then we perform the necessary subtraction to get the answer of .