10.5 Writing Slope-Intercept Equations of Lines. CORD Math Mrs. Spitz Fall 2006. Objectives:. Write a linear equation in slope-intercept form given the slope of a line and the coordinates of a point on the line, and
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
10.5 Writing Slope-Intercept Equations of Lines
y = mx + b Use slope-intercept form
y = 3x + b The slope is 3
-2 = 3(4) + b Substitute 4 for x and -2 for y
-2 = 12 + b Solve for b
-14 = b
The slope-intercept form of the equation of the line is y = 3x + (-14) or y = 3x – 14.
The slope-intercept form of the equation of the line is y = 3x + (-14) or y = 3x – 14. In standard form:
y = 3x – 14 Slope-intercept form
-3x + y = -14 Subtract x from both sides
3x – y = 14 Multiply by -1 to change the sign of the leading coefficient in front of x.
(-1, 7), (8, -2) are the two points. m = -1
y = mx + b slope intercept form
y = -1x + b substitute -1 for m
7 = -1(-1) + b substitute 7 for y and -1 for x
7 = 1 + b Distribute
6 = b Solve for b
Equation of the line is y = -x + 6
Start with slope
y = mx + b
y = 18.022x + b
Substitute 18.022 for slope, m
Substitute 10.8 for y and 7.6 for x
10.8 = 18.022(7.6) + b
10.8 = 136.967 + b
Subtract 136.067 from both sides
-126.167 = b
Equation of the line is y = 18.022x – 126.167
So you could just look at the graph and count, right? Rise over run. You know its negative because of the way it’s facing. So count.
1, 2 , 3 , 4 down
1, 2 , 3 over to the right
You could also use the slope formula with the points (0, 4) and (3, 0)
Simply a matter of following the formula from there.
y = mx + b
Rewrite the equation as:
Rewrite the equation in standard form as follows: