|
Question 595454: Write in slope-intercept form the equation of the line that passes through the given points.
(-2,-8),(-1,0)
Answer by math-vortex(648)   (Show Source):
You can put this solution on YOUR website! Write in slope-intercept form the equation of the line that passes through the given points.
(-2,-8),(-1,0)
Hi, there!
.
A linear equation in slope-intercept form is written as y = mx + b, where m is the slope and b is the y-intercept. Here, you have two points on the line, but you need to find the slope and the y-intercept.
.
[I] Find the slope of the line.
The definition of the slope is the change in y over the change in x. So, we find the difference between the y-values in the two points, the difference in the x-values, and then divide.
.
Now we know that the slope of the line m is 8. We can substitute 8 for m in the slope-intercept equation.
.
[II] Find the y-intercept.
Since both the points on the line make the equation true, we can substitute the x- and y-values for one of the points into the equation and solve for b. You can use either one. I'll use (-1,0).
.
.
The y-intercept for this equation is 8. Substitute 8 for b in the slope intercept equation.
.
[III] Check your answer.
It's always a good idea to check your work. We need to make sure that both points are solutions for this equation. We substitute the x- and y-values into the equation.
.
Check (-2,-8).
Bingo!!!
.
Check (-1,0).
Winner, winner, chicken dinner!!!
.
That's it. The equation of the line that passes through(-2,-8),(-1,0) is y=8x+8.
.
Feel free to email me if you have questions about my explanation.
.
Mrs.Figgy
math.in.the.vortex@gmail.com
|
|
|
| |
