SOLUTION: How do I graph a line using the slope of m=1/3 and point (3,-1)?

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Question 223927: How do I graph a line using the slope of m=1/3 and point (3,-1)?
Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
How do I graph a line using the slope of m=1/3 and point (3,-1)?
Step 1. The slope m is given as

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

Step 2. Let (x1,y1)=(3,-1) or x1=2 and y1=1 . Let other point be ((x2,y2)=(x,y) or x2=x and y2=y.

Step 3. Now we're given m=2. Substituting above values and variables in the slope equation m yields the following steps:

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

1%2F3=%28y-%28-1%29%29%2F%28x-3%29

Step 4. Multiply x-3 to both sides to get rid of denominator on right side of equation.

%28x-3%29%2F3=y%2B1

x%2F3-3%2F3=y%2B1

x%2F3-1=y%2B1

Step 5. Now add -1 to both sides of equation to solve for y.

x%2F3-1%2B%28-1%29=y%2B1%2B%28-1%29

x%2F3-2=y

The slope m=1/3 and y-intercept is -2 at point (0,-2).


Now you have two points (0,-2) and (3,-1) to draw a line.

Note: the above equation can be rewritten as
x%2F3-y=2 Note in this form: when y=0 then x=6 at point (6,0).

And the graph is shown below which is consistent with the above steps.

Solved by pluggable solver: DESCRIBE a linear EQUATION: slope, intercepts, etc
Equation 0.333333333333333+x+%2B+-1+y+=+2 describes a sloping line. For any
equation ax+by+c = 0, slope is -a%2Fb+=+-0.333333333333333%2F-1.
  • X intercept is found by setting y to 0: ax+by=c becomes ax=c. that means that x = c/a. 2/0.333333333333333 = 6.00000000000001.
  • 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 -0.333333333333333/-1 = 0.333333333333333.
  • Equation in slope-intercept form: y=0.333333333333333*x+-2.




I hope the above steps were helpful. Good luck in your studies!

Respectfully,
Dr J

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