SOLUTION: <pre>What is the point slope form with the table (X) 3,5, 7, 9 (Y)-6,2,10,18</pre>

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Question 236963:
What is the point slope form with the table 
(X) 3,5, 7, 9
(Y)-6,2,10,18

Found 3 solutions by RAY100, solver91311, Edwin McCravy:
Answer by RAY100(1637) About Me  (Show Source):
You can put this solution on YOUR website!
Let m= {18-(-6)}/ { 9- 3} = 24 /6 = 4
.
m= (y2-y1)/(x2-x1)
.
using the point slope eqn with extreme coordinate pairs
.
y-y1 = m (x-x1)
.
y-18 = 4(x-9)
.
y-18 = 4x -36,,,,,,,subtracting y,, and adding 36 to both sides
.
18 = 4x -y
.
.
checking, y=4x -18,,,,,,all coordinates match ,,,,,ok

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Step 1. Select any two pairs of and values, and then substitute these values into the formula for the slope and do the arithmetic.



Step 2. Select any of the coordinate pairs in your table and substitute and values and the calculated value of the slope from step 1 into the point-slope form of the equation of a line:



Check your answer by substituting the and values of the three pairs NOT selected in step 2 into your derived equation. Do the arithmetic and verify that you have a true statement in each case.


John


Answer by Edwin McCravy(20086) About Me  (Show Source):
You can put this solution on YOUR website!
What is the point slope form with the table 
(X) 3,5, 7, 9
(Y)-6,2,10,18

Let's plot those points and see if they are in a straight line:

 

They look like they do, judging from the above. We draw a
line through them:

 

We can pick any two points of the four points 
to find the slope of the line.  We'll get the
same slope no matter which two of the points
we pick.  Let's pick (5,2) and {9,18).

To find the slope we use the slope formula:

m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29

where x%5B1%5D=5, y%5B1%5D=2, x%5B2%5D=9, y%5B2%5D=18

m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29=%2818-2%29%2F%289-5%29=16%2F4=4

To find the equation, we use the point slope form:

y-y%5B1%5D=m%28x-x%5B1%5D%29

y-2=4%28x-5%29

and we solve for y and simplify to get the 

slope intercept form:

y-2=4x-20

y=4x-18

Edwin