Review: Writing an equation of a linePrepare to write equations for lines of best fit on scatter plots.

4 3 2 1 0In addition to level 3.0 and beyond what was taught in class, the student may: Make

connection with other concepts in math.

Make connection with other content areas.

The student will construct, interpret and identify patterns of associations for bivariate data displayed in two-way tables and scatterplots. - Write equation of line-of-best-fit. And use it to make predictions. - Calculate relative frequencies and describe their meaning.

The student will construct scatterplots and two-way tables from bivariate data. - Draw line-of-best-fit for scatter plot.- Identify patterns of associations. - Able to generally describe relationship of bivariate data displayed in a two-way table.

With help from theteacher, the student has partial success with level 2 and 3 elements.

Even with help, students have no success with investigating patterns of association with bivariate data.

Focus 7 - Learning Goal #2: The student will construct, interpret and identify patterns of associations for bivariate data displayed in two-way tables and scatterplots.

y = mx + b• Slope intercept form of an equation is the easiest equation to

write.• You will need two details: • 1. The slope (m)• 2. The y-intercept (b)

• Practice: • 1. A line has a slope of ½ and a y-intercept of (0, 4). Write the

equation of the line.• y = ½ x + 4• A line has a slope of –4/3 and a y-intercept of (0, -9). Write the

equation of the line.• y = -4/3x - 9

Write the equation from the graph.• Use the format y = mx + b• What two pieces of information

do you need?• Slope (m)• y-intercept (b)

• How can you find the slope of this line?

• -4/2 = -2• How can you find the y-

intercept?• (0, 0)• Write the equation:• y = -2x + 0 or y = -2x

Write the equation from the graph.• Use the format y = mx + b• What two pieces of information

do you need?• Slope (m)• y-intercept (b)

• How can you find the slope of this line?

• 2/1 = 2• How can you find the y-

intercept?• (0, 2)• Write the equation:• y = 2x + 2

What is another way to find the slope of a line?• Use the formula:

• Substitute your order pairs to find slope.• Practice:• Write the equation of a line that goes through the points (-

2, 7) and (2, 1) and has a y-intercept of (0, 4).• m = 1 - 7

2 - -2• Write the equation:• y = -3/2x + 4

12

12

xxyym

= -6 4

= -3 2

Write the equation of the line from the given information:

• The line contains the points (8, -3) and (2 , -6 ) and has a y-intercept of (0, -7).

• Find the slope:• m = -6 - -3

2 – 8• Write the equation:• y = ½ x - 7

= -3 -6

= 1 2