SOLUTION: How do I find the slope of the line containing the points? p1(0,2) and p2(4,-2)

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Question 213249: How do I find the slope of the line containing the points?
p1(0,2) and p2(4,-2)

Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
How do I find the slope of the line containing the points?
p1(0,2) and p2(4,-2)

However, here are the steps showing you how you can check your work with one of the points.

Step 1. The slope of the line m is given as

+m=%28y2-y1%29%2F%28x2-x1%29

where for our example is x1=0, y1=2, x2=4 and y2=-2 (think of slope=rise%2Frun). You can
choose the points the other way around but be consistent with the x and y coordinates. You will
get the same result.

Step 2. Substituting the above values in the slope equation gives

m=%28-2-2%29%2F%284-0%29

m=-4%2F4

m=-1

Step 3. The slope is calculated as -1 or m=-1

Step 4. Now use the slope equation of step 1 and choose one of the given points. I'll choose point (0,2). Letting y=y2 and x=x2 and substituting m=-1 in the slope equation given as,

+m=%28y2-y1%29%2F%28x2-x1%29


+-1=%28y-2%29%29%2F%28x-0%29

+-1=%28y-2%29%2F%28x-0%29

Step 5. Multiply both sides of equation by x to get rid of denomination found on the right side of the equation

+-1%28x%29=%28x%29%28y-2%29%2F%28x%29


+-1%28x%29=y-2


Step 6. Now simplify and put the above equation into slope-intercept form.

y=-x%2B2 ANSWER in slope-intercept form. m=-1 and y-intercept=2

Step 7. See if the other point (4,-2) or x=4 and y=-2 satisfies this equation

y=-x%2B2

-2=-4%2B2=-2 so it's ok...

In other words, you can use the other point to check your work.

Note; above equation can be also be transform into standard form as

x%2By=2

See graph below to check the above steps.

Solved by pluggable solver: DESCRIBE a linear EQUATION: slope, intercepts, etc
Equation 1+x+%2B+1+y+=+2 describes a sloping line. For any
equation ax+by+c = 0, slope is -a%2Fb+=+-1%2F1.
  • X intercept is found by setting y to 0: ax+by=c becomes ax=c. that means that x = c/a. 2/1 = 2.
  • Y intercept is found by setting x to 0: the equation becomes by=c, and therefore y = c/b. Y intercept is 2/1 = 2.
  • Slope is -1/1 = -1.
  • Equation in slope-intercept form: y=-1*x+2.
graph%28+500%2C+500%2C+2-8%2C+2%2B8%2C+2-8%2C+2%2B8%2C+-1%2Ax%2B2+%29+



I hope the above steps were helpful.

And good luck in your studies!

For free Step-By-Step Videos on Introduction to Algebra, please visit
http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit
http://www.FreedomUniversity.TV/courses/Trigonometry.

Respectfully,
Dr J