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Warm up. Last time, we were given two points, we graphed them and drew a line Now that we know what slope is (Rise/Run) , D raw a coordinate plane L abel the axes T ry to draw the following line given…. Slope =. Point on the line: (0,4). Objective.
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Warm up • Last time, we were given two points, we graphed them and drew a line • Now that we know what slope is (Rise/Run), • Draw a coordinate plane • Label the axes • Try to draw the following line given… Slope = Point on the line: (0,4)
Objective • Given a graph/table, write a line in slop-intercept form • From slope-intercept form, graph a line/make a table
Slope-intercept form y = mx + b • One way of representing a line • Useful to draw a line or make a table
Slope-intercept form y = mx + b If we are given the y-intercept is (0,5)… 5 = m(0) + b 5 = b If 5 = y-intercept, and 5 = b, then b = y-intercept!!
Slope-Intercept Form y = mx + b slope y-intercept
Identify the slope? Identify y-intercept? • y = 2x -7 • y = -4x + 14 • y = x - 1 • y = 4x • y = -3x + 3
Example 1 • Knowing y = mx + b, given the graph below, write the equation for the line in y = mx + b form
Example 2 • You try, write the given line in mx + b form
Example 3 • Given a table of values, how do we find the equation of a line in slope-intercept form?
Example 4 • Given a table of values, how do we find the equation of a line in slope-intercept form?
Example 5 • You try, given a table of values, how do we find the equation of a line in slope-intercept form?
Slope-intercept form to graph • Slope-intercept form gives us the y-intercept and slope • How do we draw a line? (hint: look back at the warm up) y = -3x - 2
Slope-intercept form to points • Find 3 points that lie on the following line and draw the line • Make an x and y table first • Plot the points, draw the line y = -3x - 2
Slope-intercept form to points • You try • Make an x and y table with 3 points y = -3x - 2