Write and graph lines in point-slope form and standard form Indicator 15 Write and graph lines in point-slope form and standard form
Point – slope form An equation of a nonvertical line with slope m and through point (x1, y1) is y – y1 = m(x – x1)
Example 1 A line passes through (8, -4) and has a slope 2/3. What is an equation in point-slope form of the line?
Example 2 What is the graph of the equation y + 7 = -4/5(x – 4)?
Example 3 Use the points (-2, -3) and (1, 4) to write an equation of a line.
Standard Form Standard form is Ax + By = C, where A, B and C are real numbers and A and B are not both zero.
Example 4 What are the x- and y-intercepts of the graph of each equation? a. 5x – 6y = 60 b. 3x + 8y = 12
Example 5 Graph 2x + 5y = 20
Example 6 What is the graph of each equation? a. x = 4 b. x = -1 c. y = 0 d. y = 1
Example 7 Write y – 2 = -1/3(x + 6) in standard form using integers.