SOLUTION: The section I'm working on is linear equations in two variables and their graphs. I need to find the slope of the line that goes through each pair of points...(1/2, 2), (-1, 1/2).

Algebra ->  Graphs -> SOLUTION: The section I'm working on is linear equations in two variables and their graphs. I need to find the slope of the line that goes through each pair of points...(1/2, 2), (-1, 1/2).      Log On


   

Question 12436: The section I'm working on is linear equations in two variables and their graphs. I need to find the slope of the line that goes through each pair of points...(1/2, 2), (-1, 1/2). I do not understand how to graph this or how to figure the slope. I have the same problem with decimals!! Any suggestions you have would be warmly welcomed!! Thank You, Allison Nilsson
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
The slope (m) of a line passing through the two points, (x1, y1) and (x2, y2) is given by:
m+=+%28y2-y1%29%2F%28x2-x1%29 Substitute the x and y-coordinates of the two given points to find the slope, m.
m+=+%28%281%2F2%29-2%29%2F%28-1-%281%2F2%29%29
m+=+%28-3%2F2%29%2F%28-3%2F2%29
m+=+1 The slope is: m = 1
To graph the line, you will need to find the equation of the line.
You can use the slope-intercept form: y = mx + b. You have just found m (=1), now, into the formula, you substitute the x and y-coordinates of either one of the two given points, then you'll solve for b, the y-intercept. Let's use the first point (1/2, 2).
y+=+mx+%2B+b
2+=+%281%29%281%2F2%29+%2B+b Simplify and solve for b.
2+=+1%2F2+%2B+b Subtract 1/2 from both sides.
3%2F2+=+b
Now you can write the equation of the line that passes through the two given points.
y+=+x+%2B+3%2F2 Let's see what the graph of this line looks like.
graph%28300%2C200%2C-5%2C5%2C-5%2C5%2Cx%2B%283%2F2%29%29