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Using slope/intercept. How do you use the slope/intercept equation to solve problems? SPI: 706.3.12. Activator:. Write the following problem in function form: 6x – 3y = 18 Y = 2x + -6 or y = 2x – 6 This form is also known as: slope/intercept: y = mx + b.
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Using slope/intercept • How do you use the slope/intercept equation to solve problems? SPI: 706.3.12
Activator: • Write the following problem in function form: 6x – 3y = 18 • Y = 2x + -6 or y = 2x – 6 • This form is also known as: slope/intercept: y = mx + b
What is slope/intercept? • Slope/intercept is the equation that relates every x coordinate with its y coordinate. It is written as “y =“ • Y = mx + b • m = slope and b = y-intercept
Once an equation is in slope/intercept form you can identify the slope as the coefficient of x and the y-intercept as the constant. • Example: y = -¼x + 7 • slope = -¼ y-intercept = 7
Matching an equation w/ a line • http://math123xyz.com/Nav/Algebra/Quick_Graph_with_Slope-Intercept_Practice.php
Graphing slope/intercept • To graph slope intercept plot a point on the y-axis or the y-intercept (The # you got for b) • Next, use the slope to find the next point. Remember to move the correct directions. • Examples:
Graph: y = 3x - 4 Insert graph
Extra Info: • Parallel lines have the same slope. • Example: y=2/3x + 5 and y=2/3x -4 • Perpendicular lines have the negative reciprocal of each others slope • Example: y=2/3x + 4 and y=-3/2x + 3
What is a parallel line to y = 1/5x + 4 • What is a perpendicular line to y=1/5 + 4