|
Question 283026: graph the line containing the given pair of points and find the slope.
(5,4),(-4,-3)
graph it on a y is -10,10 graph and x is -10 an 10 graph.
then find the slope- m=
Answer by oberobic(2304)   (Show Source):
You can put this solution on YOUR website! The slope-intercept form is: y = mx+b, where m is the slope and b is the y-intercept (the point were x=0).
.
The slope is defined as the rise over the run, which is the change in 'y' divided by the change in 'x'.
.
m = (y2-y1)/x2-x1)
.
(x1,y1) = (5,4)
(x2,y2) = (-4,-3)
.
m = (-3 -4)/(-4-5)
m = -7/-9 = 7/9
.
y = 7/9x + b
.
Substitute what we know already to find 'b'.
.
For example, we know the point (5,4) is on the line.
.
4 = 7/9(5) + b
.
Multiply through by 9 to remove the fraction
.
36 = 7(5) + 9b
36 = 35 + 9b
1 = 9b
9b = 1
b = 1/9
.
Now we can find the x-intercept, which is the point where y=0.
0 = 7/9x + 1/9
.
multiply through by 9
.
9(0) = 7x + 1
0 = 7x + 1
x = -1/7
(-1/7,0)
.
So, to summarize:
Equation is: y = 7/9x + 1/9
y-intercept is: (0, 1/9)
x-intercept is: (-1/7, 0)
.
Graphing it helps confirm your work.
.
Done
|
|
|
| |
