4-1 SLOPE INTERCEPT FORM

Y= mx + b

SLOPE

Y-intercep

t

FIND THE EQUATION

Warm-up Name:_______________Out of 400 citizens randomly surveyed, 258 stated they supported building a dog park. If the survey was unbiased, how many of the city’s 5800 citizens can be expected not to support the dog park?

What is the slope of the line that passes through (–4, 8) and (5, 2)?

Suppose y varies directly as x and y = –5 when x = 10. What is the direct variation equation that relates x and y?

Find the next two terms in the arithmetic sequence –7, –4, –1, 2, ….

A short review of Chapter 3Is the function represented by the table linear? Explain.

Out of 400 citizens randomly surveyed, 258 stated they supported building a dog park. If the survey was unbiased, how many of the city’s 5800 citizens can be expected not to support the dog park?

EQ: Why is math used to model real-world situations?

I will be able to…….Write and graph linear equations in slope-intercept from.

…Model real-world data with equations in slope-intercept form

4-1 Slope intercept form

Compare Y = kxY = mx + b

How do they differ?

How are they similar?

Graph y = –7

4-1 Slope intercept formGraph 5y = 10. What is the equation in

slope-intercept form for the line shown in the graph? Note:You need to find the slope and y-intercept of the line to write the equation.

4-1 Slope intercept formWhat is the equation in slope-intercept form for the line shown in the graph?

4-1 Real World ExampleHEALTH The ideal maximum heart rate for a 25-year-old exercising to burn fat is 117 beats per minute. For every 5 years older than 25, that ideal rate drops 3 beats per minute. A. Write a linear equation to find the ideal maximum heart rate for anyone over 25 who is exercising to burn fat.

Graph the equation.

. Find the ideal maximum heart rate for a

55-year-old person exercising to burn fat.

4-1 Real world exampleThe amount of money spent on Christmas gifts has increased by an average of $150,000 ($0.15 million) per year since 1986. Consumers spent $3 million in 1986. Write a linear equation to find the average amount D spent for any year n since 1986.

The amount of money spent on Christmas gifts has increased by an average of $150,000 ($0.15 million) per year since 1986. Consumers spent $3 million in 1986. Graph the equation.

The amount of money spent on Christmas gifts has increased by an average of $150,000 ($0.15 million) per year since 1986. Consumers spent $3 million in 1986. Find the amount spent by consumers in 1999.