Slope Intercept Form

What is the y-intercept of the line whose equation is y =1/2 x - 3?

-3

Find the slope of the line whose equation is 5y = x - 3.

1/5

The line of best fit drawn on the plot shown is used to predict the number of tickets sold on a certain day. Use the two points shown on the line of best fit to calculate its slope to the nearest tenth.

4.2

LinearEquation

an open sentence whose graph is a line; the general form for such an equation is Ax + By + C = 0

y-intercept

the point where the line crosses the y-axis

slope

the rate of change of a line; change in y over change in x; rise over run

Which of the following lines has a slope of -1/2?

x + 2y = 0

Write the equation 2x - 3y = 6 in slope-intercept form.

y = 2/3x - 2

Write the equation for 5x + 2y = 3 in slope-intercept form.

y= -5/2x + 3/2

slope-intercept form

y = mx + b form of a linear equation

What is the equation of this best line of fit? y = 5x + 5 y = x + 5 y = 5x +25 y = x + 125

y = x + 5

The owner writes a line of best fit equation, shown below, to model the relationship between profit earned and month. y = 2,500x - 2,500 Explain how you know that the line of best fit equation is appropriate, mentioning both the slope and y-intercept in your response.

Collinear means that when you connect these points, you get a straight line. These points are at months 1, 2, 3, and 9. Then of these points, I chose 2 points to find the slope between them. Point 1 = (1, 0) Point 2 = (2, 2.5) or (2, 2500) because profit is measured in thousands These are the first two points. Slope = (2500 - 0) / (2 - 1) Slope = 2500 / 1 Slope = 2500 Then I plug in the slope and values of point 1 into the slope-intercept form of the line. y = mx + b 0 = 2500(1) + b Solve for b. 0 = 2500 + b -2500 = b