Equality Adding and Subtracting

Which property of equality would you use to answer the following equation?
x + 9 = 17

• Addition property of equality

• Subtraction property of equality

• Multiplication property of equality

• 8

Evaluate:
18 = c + 0.8

• c = 18.08

• c = 17

• c = 17.2

• c = -17.2

Which property would you use to solve: x-23=100

• Addition property of equality

• Subtraction property of equality

• Multiplication property of equality

• Distributive property

What is the inverse operation of adding?

• Adding

• Subtracting

• Multiplying

• Dividing

Addition Property of Equality

• adding the coefficients of terms with the same variable

• adding the same number to both sides of the equation

• subtracting the same number from both sides of the equation

• adding the numbers and keeping the sign

Step 1 : 5(x + 2) = 8 - x  

Step 2:  5x + 10 = 8 - x 

                     - 10  -10

Step 3: 5x = 6 - x
Describe the property shown between step 2 and 3

• Addition Property of Equality

• Multiplication Property of Equality

• Subtraction Property of Equality
  

• Distributive Property

Step 1 : 5(x + 2) = 8 - x  Step 2:  5x + 10 = 8 - x                        - 10  -10Step 3: 5x = 6 - x
            + x        + x
Step 4: 6x = 6
Describe the property shown between step 3 and 4

• Addition Property of Equality

• Multiplication Property of Equality

• Subtraction Property of Equality
  

• Distributive Property

3x + 4 - 2x = 5 - 2x + 1

• no solution

• infinite number of solutions

• x = 0

What is the answer? 3x + 2 = -5x + 10

• x = 1

• x = -1

• x = 6

• x = -6

Answer explanation

If we add 5x to both sides, we get;

8x + 2 = 10.

Then we need to subtract 2 from both sides to get;

8x = 8.

Finally we divide both sides by what is attached to the x, which in this case is 8.

8x/8 = x and 8/8 = 1 so x=1

If I wanted to start to simplify this equation what would I do in order to get variables on one side and constants on the other?

• Move the 2x to the other side of the equation by adding it to both sides.

• Move the 6 to the other side of the equation by adding it to both side.

• Move the 2x to the other side of the equation by subtracting it from both sides.

• Move the 6 to the other side of the equation by subtracting it from both sides.

Answer explanation

If we move the 2x, then all terms with a variable will be on the right, and all constants will be on the left. Since the 2x is positive on the left, we want to do the opposite and subtract it from both sides.