Do Now 1/25/10Do Now 1/25/10 Take out HW from Friday.Take out HW from Friday.

Text page 245, #16-34 evens, #37Text page 245, #16-34 evens, #37

Copy HW in your planner.Copy HW in your planner. Text page 249, #12-32 evensText page 249, #12-32 evens

In your notebook, answer the following In your notebook, answer the following question. Draw a picture of what an question. Draw a picture of what an equation looks like to you. Then give an equation looks like to you. Then give an example of a multiplication and division example of a multiplication and division equation.equation.

HomeworkHomeworkText p. 245, #16-34 evens, #37Text p. 245, #16-34 evens, #37

16) 39/4016) 39/40 18) -14/2718) -14/27 20) 6 1/420) 6 1/4 22) -20 2/322) -20 2/3 24) -42 1/224) -42 1/2 26) 10/84726) 10/847 28) 5 bookmarks28) 5 bookmarks

30) 6/730) 6/7 32) -20/33 32) -20/33 34) 1 2/334) 1 2/3 37) 2237) 22

EQUATION – EQUATION – mathematical sentence formed mathematical sentence formed by placing an “=“ between two by placing an “=“ between two expressionsexpressions

yy – 8 = 12 – 8 = 12 22 = 14 + z22 = 14 + z

11a = 12111a = 121 5 ÷ x = 30 5 ÷ x = 30

Remember this???

Remember this???

EquationEquation

Like a scale, the Like a scale, the left side and right left side and right side must be the side must be the same in order to be same in order to be balanced!balanced!

+ 7 = 10+ 7 = 10Left side Right side

xx

‘‘x’ has to be 3 in order x’ has to be 3 in order to make the equation to make the equation balanced.balanced.

Remember this???

EquationEquation

Like a scale, the left Like a scale, the left side and right side must side and right side must be the same in order to be the same in order to be be balanced!balanced!

= 10= 10

Left side Right side

xx4477

ObjectiveObjective

SWBAT use multiplicative inverses SWBAT use multiplicative inverses to solve equations.to solve equations.

Section 5.6, “Using Section 5.6, “Using Multiplicative Inverses to Multiplicative Inverses to

Solve Equations” Solve Equations”

Multiplicative Inverse PropertyMultiplicative Inverse Property

To solve an equation that has a To solve an equation that has a fractional coefficient, you can multiply fractional coefficient, you can multiply each side of the equation by the each side of the equation by the fraction’s multiplicative inverse. fraction’s multiplicative inverse.

MULTIPLICATIVEMULTIPLICATIVEINVERSEINVERSE

RECIPROCALRECIPROCAL==

MULTIPLICATIVE MULTIPLICATIVE INVERSE–INVERSE–

the product of a number and the product of a number and its multiplicative inverse is 1. its multiplicative inverse is 1.

3

21

6

6

2

3

7

41

28

28

4

7

127

4x

127

4x

21x41

7121

x

Solve for x.Solve for x.

Multiply each side of the equation Multiply each side of the equation by the by the MULTIPLICATIVE INVERSEMULTIPLICATIVE INVERSE of 4/7 of 4/7

Divide (cancel) common factorsDivide (cancel) common factors

11

-3-3

4

7121x

MultiplyMultiply

4

7

4

7

Try It Out!!Try It Out!!Solve Solve

206

5x 20

6

5x

5

6

5

624x

x22

17

11

4 x

22

17

11

4

17

22

17

22

17

8x

Solving Multi-Step Solving Multi-Step Equations Equations

How can you get the “unknown” by How can you get the “unknown” by itself?itself?

Solving Equations with Variables on Both SidesSolving Equations with Variables on Both Sides

STEP 1- Use distributive property and combine like terms.STEP 1- Use distributive property and combine like terms.STEP 2- Collect variables on one side of the equation.STEP 2- Collect variables on one side of the equation.STEP 3- “Undo” addition and/or subtraction.STEP 3- “Undo” addition and/or subtraction.STEP 4- “Undo” multiplication and/or division.STEP 4- “Undo” multiplication and/or division.STEP 5- Solve for the variable.STEP 5- Solve for the variable.STEP 6- Check your work.STEP 6- Check your work.

Remember this?

??

Remember this?

??

3

1

5

4

15

11 x

15

7

15

11 x

11

7x

Solve for x.Solve for x.

Multiply each side of the equation Multiply each side of the equation by the by the MULTIPLICATIVE MULTIPLICATIVE INVERSEINVERSE of -7/15 of -7/15

Divide (cancel) Divide (cancel) common factorscommon factors

11

15

15

71x

MultiplyMultiply

11

15

11

15

5

4

3

1

5

4

5

4

15

11

x Subtract 4/5 from each side.Subtract 4/5 from each side.

Write fractions using LCDWrite fractions using LCD15

12

15

5

11

-1-1

Try It Out!!Try It Out!!Solve Solve

204

316 n

3

15n

6

5

2

1

3

2 p

2

1p

x16

5

6

5

48

5

3

12x

Homework Homework

Text page 249, #12-32 evensText page 249, #12-32 evens