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Graphing Linear Equations. In Slope-Intercept Form. We have already seen that linear equations have two variables and when we plot all the (x,y) pairs that make the equation true we get a line.
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Graphing Linear Equations In Slope-Intercept Form
We have already seen that linear equations have two variables and when we plot all the (x,y) pairs that make the equation true we get a line. In this section, instead of making a table, evaluating y for each x, plotting the points and making a line, we will use The Slope-Intercept Form of the equation to graph the line.
The formula for Slope-Intercept Form is: • ‘b’ is the y-intercept. • ‘m’ is the slope. On the next three slides we will graph the three equations: using their y-intercepts and slopes.
right 1 up 2 right 1 up 2
down 1 down 1 right 1 right 1
right 2 up 3 right 2 up 3
Sometimes we must solve the equation for y before we can graph it.
down 2 down 2 right 1 right 1 1) Plot the y-intercept as a point on the y-axis. The constant, b = 3, so the y-intercept = 3. 2) Plot more points by counting the slope up the numerator (down if negative) and right the denominator. The coefficient, m = -2, so the slope = -2/1.
HW • pg. 298 #12 to 26 even