SOLUTION: I'm about ready to give up. The question is: Write the equation of the line passing through each of the given pair of points. Write your result in slope-intercept form, where possi

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Question 38452This question is from textbook Beginning Algebra
: I'm about ready to give up. The question is: Write the equation of the line passing through each of the given pair of points. Write your result in slope-intercept form, where possible. (-1, 3) and (4, -2).
Thanks so much!This question is from textbook Beginning Algebra

Answer by longjonsilver(2297) About Me  (Show Source):
You can put this solution on YOUR website!
look at the lessons i have written on this topic. They will help you.

Anyway...
a straight line is of the form y=mx + c. We need to find the value of m (the gradient) and c (the y-intercept).

Right then. Gradient first.
gradient, m = (change in y)/(change in x)
+m+=+%283+-+%28-2%29%29%2F%28-1+-+4%29+
+m+=+%283%2B2%29%2F%28-5%29+
+m+=+%285%29%2F%28-5%29+
--> m = -1

so we now have y=-x+c

Now for c: we need to know x and y to find c. We do...we have 2 possible pairs of x and y: the 2 sets of coordinates. Pick the "easiest" pair. I will pick (-1,3):

y=-x+c
3=-(-1)+c
3 = 1+c
2 = c

--> equation is y=-x+2

AND NOW CHECK WITH THE OTHER SET OF COORDINATES, here (4,-2): if we put x=4 into the equation, we shout get y=-2 out of it:

y=-x+2
y=-4+2
y = -2... CORRECT

so now i KNOW i am correct

jon.