Question 87565: Write the equation of a line in slope intercept form given the following points
(-3 7) and (4 -7)
Kind of confused here. Can you help?
Found 2 solutions by checkley75, Earlsdon:
Answer by checkley75(3666)   (Show Source):
You can put this solution on YOUR website! FIRST WE FIND THE SLOPE (Y2-Y1)/(X2-X1)=(-7-7)/(4+3)=-14/7=-2 FOR THE SLOPE (m)
NOW SUBSTITUTE X & Y IN THE LINE EQUATION Y=mX+y & SOLVE FOR (b) THE Y INTERCEPT.
7=-3*-2+b
7=6+b
b=7-6
b=1 Y INTERCEPT.
THEN THE EQUATION IS Y=-2X+1
Answer by Earlsdon(6294) (Show Source):
You can put this solution on YOUR website! Write the equation in slope-intercept form:  for the line containing the two points (-3, 7) and (4, -7).
You can find the slope, m, by:  where: ( ,  ) = (-3, 7) and ( ,  ) = (4, -7)
So now you have:
 Next, you need to find the value of the y-intercept, b.
To do this, you will substitute the x- and y-coordinate values from either one of the two given points into this equation and solve for b.
Let's choose the second point (4, -7) so we'll substitute x = 4 and y = -7 and solve for b.
 Simplify.
 Add 8 to both sides.
Now you can write the final equation in the point-slope form.
 ...and there it is!
And here's what the graph of this line would look like:
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