Solving Equations with Adding/Subtraction

Solving Equations with Adding/Subtraction

CH 3.3

​Equivalent Equations

​Two equations that have the same solution.

​

​5 = 5

​2 + 1 = 1 + 2

​3 + 7 = 5 + 5

​Property of Equality

​Addition/Subtraction Property of Equality

Adding/Subtracting the same numbers to each side of an equation produces an equivalent equation.

​

​a = b then, a + c = b + c

​a = b then, a - c = b - c

Multiple Choice

If a = b, would they be equivalent if you add 8 to both sides?

a + 8 = b + 8

• Yes

• No

• Depends on what a and b equals

• If a is negative

​Property of Equality

​Addition and subtraction are inverse operations.

​

Multiple Choice

What is the inverse of addition?

• Division

• Multiplication

• Subtraction

• Exponent

Multiple Choice

What is another word for inverse?

• Difference

• Opposite

• Variable

• Quotient

​Property of Equality

​To solve an equation, you must isolate the variable using inverse operations on both sides of the equation.

​

​x + 4 = 12

​Property of Equality

Multiple Choice

What does the word isolate mean?

• To complete

• To turn into a fraction

• To add or subtract

• To get by itself

Multiple Choice

When solving an equation, what do you want to do to the variable?

• Add it to the constant

• Isolate it

• Eliminate it

• Substitute a random value for it

Fill in the Blanks

Solve.

g - 3 = 9

Multiple Choice

Solve.

h + 2 = 6

• 3

• 4

• 8

• 12

Multiple Choice

Solve.

x - 5 = -9

• -4

• -14

• 4

• 14

Multiple Choice

Solve.

w + 13.2 = 10.4

• -2.8

• 23.6

• -3.2

• 4.2

​Property of Equality

6 - x = 12

​

​

​10 - p = -8

Multiple Choice

Solve.

4 - x = 5

• 9

• 1

• -1

• 20

Multiple Choice

Solve.

10 - m = -10

• 20

• 0

• -20

• 1

​Property of Equality

27 is 12 more than a number x.

​

​

​

The difference of a number p and -9 is 12

Multiple Choice

What word can I look out for the would mean equals?

• is

• sum

• difference

• product

Multiple Select

Choose all the words that could refer to an addition problem.

• sum

• total

• difference

• combined

Multiple Choice

What equation represents the word problem?

The difference between the numbers p and 3 is 10.

• p - 3 = 10

• 10 - 3 = p

• 10 - p = 3

• 10 - 3p

Multiple Choice

What equation represents the word problem?

The sum of a number x and 8 is 12.

• x + 8 = 12

• 12 + 8 = x

• 12 + x = 8

• x + 12 + 8

Multiple Choice

Solve.

16 is 12 more than a number x

• 4

• 28

• -4

• 6

Multiple Choice

Solve.

35 less than a number m is - 72

• -37

• -107

• 35

• 107

Poll

How comfortable are you with solving equations with addition and subtraction?

• Not at all

• A little

• Good so far

• I could take a quiz right now