Chapter 3

Solving and Checking Equations

Solving, Checking and Graphing Inequalities

Do Now 11/6

1. What is the difference between an expression and an equation?

Equation – a mathematical sentence formed by placing an equal sign between two expressions

Expression – consist of numbers, variables and operations. (NO EQUAL SIGN)

2. Write the inverse operations down with an example of how to solve using them:

Solving 1- Step Equations

Use inverse operations:Addition/Subtraction

+/-Multiplication/Division

*/ ÷ Squared/Square root

x2 / √

Checking Equations

1. Re-write original equation

2. Substitute value(s) in for variable(s)

3. Solve using Order of Operations

Solve and Check:

1) n + 10 = -23

2) 42= -7x

3) r ÷ 3 = -8

4) n –(-15) = 7

5) 3= . t .

-5

Solve and Check

1) -13 = r + 9

2) -4x = 12

3) 15 = m -8

4) r – (-8) = 24

Do Now 11/9

Solve and CHECK

1) 9 = w +(-16)

2) -3x = -18

3) 2 = y .

-7

4) m – 3 = -4

Solving 2- step equations

Use inverse operations

FIRST - Addition/Subtraction +/-

SECOND- Multiplication/Division */ ÷

(Order of Operations backwards)

Checking 2- Step Equations

1. Re-write original equation

2. Substitute value(s) in for variable(s)

3. Solve using Order of Operations

Solve and Check

1. 3x + 10= -20

2. 13 = 2p – 5

Solve and Check

3) 19 + 8v = 43

4) G + 6 = -2 9

Do Now 11/10

Solve and Check:

1. C + 34= 46 -8

2. -8 = 72 – 5t

Solve and Check

1. C + 26 = 46 -10

2. -82 = 53 – 5t

3. -33 = -15t -12

4. 8x – (-4) = 20

Do Now 11/12

1. Take out Apple

Solve and Check:

2. 6x + 4 = 22

3. 18 = 2r - 6

Using Key words- Write, Solve and Check equations:

1. The sum of 4 times a number and 3 is 11. What is the number?

2. 6 less than 2 times a number is 18. What is the number?

3. Our class spends $46 on supplies for gingerbread houses. How many houses must we sell at $9 each to make a profit of $100?

Do Now 11/18 – Fill in chart

Perimeter Area

Square

Rectangle

Triangle

To use formulas:

1. Write formula

2. Substitute values

3. Solve using Order of Operations

A= units squared = 44mm2

P= units not squared= 32mm

Find the Perimeter and Area of the shapes:

4 ft

10 ft

3 c

m

9 cm

12 yd

5 y

d

14

m3 m

1. 2.

3. 4.

12 ft

15 m

15 m

Find the missing dimension of the shapes

1. A= 18 ft2

2. A= 32mm2

6 ft

8 mm

Do Now 11/19: Find the missing dimension of the shape

1) A = 30 in2

10

in

x

Graphing Inequalities

> Greater Than

< Less Than

= Equal

≤ Less than or Equal

≥ Greater Than or Equal

Solving and Graphing Inequalities

1. n< 5

2

2. -20 > 4x

Solving and Graphing Inequalities

3. p - 2 ≥ -8

4. -17 ≤ y + -13

Do Now 11/20 – Solve and Graph

1. p – (-6) ≥ 4

2. -8 > -11 + m

3. N ≤ -34

4. -6r < 36

Solving and Graphing Inequalities

You are participating in Ms. Bradshaw’s stock market game. The Hot Topic stock you want to buy costs $13.00 per share. You can’t spend more than $325 without going into debt. Write, solve and graph an inequality to see how many shares you can buy.

11/23 – Do Now Solve and Graph

1. 3 + t < 5

2. -5 ≥ 4 + m

Solve and Graph

1. 64< 14 + 3x

2. -6g  -  9   ≥  137

3. 12  <  t +  2

2

You are participating in Ms. Bradshaw’s stock market game. The Hot Topic stock you want to buy costs $13.00 per share. You can’t spend more than $325 without going into debt. Write, solve and graph an inequality to see how many shares you can buy.

You are saving money to buy a wii. You already have $45.00 and you earn $42.00 per week mowing lawns. If a wii costs $250, write, solve and graph an inequality to show how many weeks you need to save to buy the wii.

Gio needs an average math score of at least an 85 to qualify for a scholarship. His first two test scores were 78 and 86. There is one more test to take. What is the lowest he can score and still qualify?

Chapter 3 Test – Tuesday Dec 1 1 – step equations – solve and check 2 - step equations – solve and check

Solve: Use inverse operations (+/-) ( */ ÷ ) Follow order of operations backwards

First- (+/-) Second - ( */ ÷ ) Third exponents Forth Parenthesis

Check: 1. Re-write equation 2. Substitute 3. Solve – Using Order of Operations

Chapter 3 Test – Tuesday Dec 1

Inequalities Use inverse operations When you multiply or divide by a negative the

inequality sign flips (<, >) (≥, ≤) Area and Perimeter (Squares, Rectangles,

Triangles) Find missing side Find area Find Perimeter

Translating Verbal Expressions into equations Word Problems