WARM – UP #51. Graph 4x – 5y = -20

What is the x-intercept?

What is the y-intercept?

2. Graph y = -3x + 2

3. Graph x = -4

WARM – UP #5 SOLUTIONS1. Graph 4x – 5y = -20

x-intercept (y = 0) 4x - 5(0) = -20

4x = -20 x = -5

(-5, 0)

y-intercept (x = 0)

4(0) - 5y = -20

-5y = -20

y = 4

(0, 4)

WARM – UP #5 SOLUTIONS2. Graph y = -3x + 2

Slope = -3

y-int: (0, 2)

WARM – UP #5 SOLUTIONS4. Graph x = -4

LESSON 2-5 USING LINEAR MODELS

Algebra II

LEARNING OBJECTIVE

To write linear equations that model real-world data

To make predictions from linear models

Scatter Plot – graph that relates two sets of data by plotting the data as ordered pairs

Correlation – strength of the relationship between data sets

Correlation Coefficient r – indicates strength of correlation

Positive Correlationr is closer to 1

Negative Correlationr is closer to -1

No Correlation r is closer to 0

Line of Best Fit – the trend line that gives the most accurate model of related data

To write the equation of the line:

-Find slope of the line

-Use the slope and a point to write an equation of the line

1. a. Make a scatter plot

b. Sketch a line of best fit

c. What is the correlation?

d. What is the equation for the line of best fit?

A. SCATTER PLOT

B. LINE OF BEST FIT

C. STRONG NEGATIVE CORRELATION!

D. LINE OF BEST FITUse 2 points (0, 100) & (3, 75)

y = -8.3x + 100

2. Using #1’s linear model, predict what your test score will be if you spend 10 hours on the computer daily.

y = -8.3x + 100

y = -8.3(10) + 100

y = -83 + 100

y = 17

17%!! Spend more time studying and less time on the computer!!

TICKET OUT THE DOOR The table shows population and licensed driver from a recent year.

a. Make a

scatter plot

b. Sketch a

line of best

fit

c. Is the correlation strong or weak? Explain.

ASSIGNMENT:

PG. 96 # 7 – 11, 14 - 17, 27 - 29

Don’t Cry. You

got this!!!