SOLUTION: I really need your help. Write the equation in slope-intercept form of the line passing through each pair of points: (6,-2) and (3,-4) Write the equation in slope-intercept f

Algebra ->  Linear-equations -> SOLUTION: I really need your help. Write the equation in slope-intercept form of the line passing through each pair of points: (6,-2) and (3,-4) Write the equation in slope-intercept f      Log On


   

Question 55967: I really need your help.
Write the equation in slope-intercept form of the line passing through each pair of points: (6,-2) and (3,-4)
Write the equation in slope-intercept form of the line passing through each pair of points: (-8,2) and (0,6)
Thank you...
Found 3 solutions by Lacey020991, Hook, stanbon:
Answer by Lacey020991(49) About Me  (Show Source):
You can put this solution on YOUR website!
Question 1:
The formula with a line that has a slope of m and a y-intercept (the value of y where the line crosses the y-axis) of b is
.
y = mx + b
.
To find the slope, m, of the line is the change in y divided by the change in x.
.
x1= 6 ; y1= -2
x2= 3 ; y2= -4
.
m+=+%28y2-y1%29+%2F+%28x2-x1%29
m+=+%28-4+-+-2%29+%2F+%283+-+6%29
m=+%28-2%29%2F-3
m=+2%2F3
.
Now, to find the y-intercept, b, use one of the points to get the x and y values, and solve for b.
Remember:
x1= 6 ; y1= -2
x2= 3 ; y2= -4
m=2%2F3
.
y1 = mx1 + b
b = y1 - mx1
b = -2 - 2%2F3 (6)
b = -6
.
Now that we know the slope, m = 2%2F3, and the y-intercept, b = -6, we can write the equation of the line:
.
y= %282%2F3%29x+-6
.
Question 2:
.
We would do the same process:
.
x1= -8 ; y1= 2
x2= 2 ; y2= 6
.
m+=+%28y2-y1%29+%2F+%28x2-x1%29
m+=+%286+-+2%29+%2F+%282+-+-8%29
m=+4%2F10
m=+2%2F5
.
y1 = mx1 + b
b = y1 - mx1
.
b+=+2+-+%282%2F5%29%28-8%29
b = 5.2
.
Now that we know the slope, m+=+%282%2F5%29, and the y-intercept, b = 5.2, we can write the equation of the line:
.
y=+%282%2F5%29x%2B5.2
.
**Remember to always check your answer**

Answer by Hook(36) About Me  (Show Source):
You can put this solution on YOUR website!
Remember that the slope-intercept form is y=mx%2Bb. On these, you just have to find m and b. Also remember that m+=+%28y2-y1%29%2F%28x2-x1%29
Let's find m for your first problem:
m+=+%28y2-y1%29%2F%28x2-x1%29
m+=+%28-4--2%29%2F%283-6%29
m+=+%28-2%29%2F-3
m+=+2%2F3
Ok, now we have to find b. Our equation so far is y+=+%282%2F3%29x+%2B+b. If we plug one of the points (doesn't matter which one...) in for x and y, we can solve for b.
y+=+%282%2F3%29x+%2B+b
Plugging in (3,-4)
-4=%282%2F3%29%283%29%2Bb
-4=2%2Bb
-6+=+b
Alright. Our equation is y+=+%282%2F3%29m+-+6!!!
There. I did the first one. You can do the second one

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Write the equation in slope-intercept form of the line passing through each pair of points: (6,-2) and (3,-4)
You want y=mx+b; need to find m and b
m=[-2--4]/[3-6]=-2/3
b=-4+(2/3)3
b=-2
So, equation is y=(-2/3)x-2
----------------------
Write the equation in slope-intercept form of the line passing through each pair of points: (-8,2) and (0,6)
m=[6-2]/[0--8)]=4/8 = 1/2
6=(1/2)0+b
b=6
So, equation is y=(1/2)x+6
Cheers,
Stan H.