Lesson 5-2: Solve Two-Step Equations

Lesson 5-2: Solve Two-Step Equations

Questions 1-10 on pages 272 and 273

Open Ended

What does it mean to solve an equation?

Multiple Choice

Question #1

• They are completely different

• Both use inverse operations to solve

• one step equations use properties of equality but two step do not

• They are exactly the same thing

Look at #2...

• Why are both bars in the model the same length?

• The bar diagram represents both sides of an equation. Equations are = so the bars have to be the same length to show that visually.

Multiple Choice

Question #2

• Bar diagrams do not allow us to solve equations

• First add 13 to 3x. Then add 3 to x. Then put everything together to get 20x.

• First add 13 and 3 to show that 4x is equal to 16. Then divide 16 into 4 equal pieces to show that x = 4.

• Do 13 divided by 3 and get 4 $\frac{1}{3}$

Multiple Choice

Question #3

• I can substitute 14 for p and check that he equation is true.

• I can substitute 14 for the 72 and check.

• I can substitute 14 for the 6 and check.

• There is no way we can check other people's work.

Before we answer #4...

• How do we multiply fractions?

• What do we do if one of the fractions is a mixed number?

Multiple Choice

Question #4a

• 2c = 1 $\frac{1}{3}$

• 2 + 2 = c ( 1 $\frac{1}{3}$ )

• 2c + 4 = 4 ( 1/3)

• 2 + c = 2 ( 1 $\frac{1}{3}$ )

Before we do part b...

• what is 2 * 1 $\frac{1}{3}$  ? 

•  $\frac{8}{3}$  

Multiple Choice

Question #4b

• c = 2

• c = 2/3

• c = 3

• c = 6/3

Multiple Choice

Question #5a

• 4n + 3 = 47

• 4n = 50

• 3n + 4 = 47

• 47n = 7

Multiple Choice

Question #5b

• 12.5

• 11

• 200

• the answer is not here

Multiple Choice

Question #6

• 7

• 1

• 4

• 0

Multiple Choice

Question #7

• 85

• 3

• 75

• 2.5

Thinking about #7...

• Frank solved the problem the way you see on the dry erase board. What did he do wrong?

• He did not subtract 2 from both sides.

Multiple Choice

Question #8

• x = 3

• x = 4

• x = 5

• x = 7

Multiple Choice

Question #9

• Daniel spent $38

• Daniel spent $16

• Daniel spent $12.66

• Daniel spent $9.33

Multiple Choice

Question #10

• 2.7

• 1.75

• -4.5

• 4.5

Complete problems 11 - 17 with your group

The rest of page 273 and page 274.