MONDAY, DECEMBER 5TH

o Please grab a new warm up!

o Did you write down the homework?

Warm UpSolve each proportion

1. 2. 9

11 7

x

7

12 9

x

CORNY JOKE OF THE DAY

Why are most baseball games held at night?

Because the bats sleep

during the day

DID ANYONE TRY THIS?

For most people, the ratio of thelength of their head to their total

height is 1:7. Use proportions to testyour measurements and see if they

match this ratio.

WEEKLY REVIEW ANSWERS

One week to our final!!!!!!!!!!

RATIONAL NUMBERS

-11-2.44-1 ¼ -54

EVALUATING

2-1.25 1/64-1/86

ALGEBRA

5 1/3 14/15-2 13/28-17.577

WRITE A RULE

-2n-15n + 1 EXC-10n-15

CHECKPOINT ANSWERS

Graphing

0You usually call me a

__________________________.

The numbers to the right of my zero are always______________.

The numbers to the left of my zero are always______________.

You can think of me as a

_________________________.

The numbers above my zero are always______________.

The numbers below my zero are always______________.

00

What do you get when you cross a number line with a thermometer?

In a coordinate plane the “number line” is called the _______________.

In a coordinate plane the “thermometer” is called the _______________.

THE 4 QUADRANTS USING:I, II, III, IV

There are 4 Quadrants

on a coordinate

plane!!

III

III IV

(8,5)

(-4,7)

(0,4)

(6,-9)

(-5,8)

(-7,0)

DirectVariation

EQUIVALENT PROPORTIONS IS DIRECT VARIATION!!! !

2/12 is the same as 4 to 24 is the same as 6 to 36….etc. So, this varies proportionally!

X 2 4 6 8 9y 12 24 36 48 54

NOT A DIRECT VARIATION

1/6 is not the same as 2/8 or 3/10 or ……….

X 1 2 3 4 5y 6 8 10 12 14

A direct-variation equation is always linear and always contains the point (0, 0).

The variables x and y either increase together or decrease together.

Helpful Hint

SITUATIONS THAT CHANGE PROPORTIONALLY

Ms. Evans Example: Movie tickets and the total amount of money it’s going to cost

Zero Tickets=Zero dollars

The more movie tickets I buy, the more total money I will have to pay!

GROUP DISCUSSION

Think of a situation that has a direct Variation!

FINDING THE CONSTANT (K) IN THE EQUATION

Y = kx Find k when:

1. y=5x2. Y=1/2x3. Y=11x4. Y=.74x5. Y=4/5x

FINDING THE CONSTANT (K) IN A TABLE

K=y/xX 2 4 6 8 9y 12 24 36 48 54

126

2

yk

x

YOU TRY!2.

3.

X 1 2 3 4y 8 16 24 32

X 50 40 30 20y 5 4 3 2

CAN YOU MATCH THE CORRECT PROPORTION

a. Y = 3x b. x=3y

c. y=5x d. x=5y

X 3 6 9 12y 15 30 45 60

USING DIRECT VARIATION TO SOLVE PROBLEMS

The equation below can be used to determine how many boys, y, are in sixth-grade class that has x girls. Y=5/6x

If there are 12 girls in the class, how many boys are in the class?

a. 8 b. 10 c. 12 d. 18