SOLUTION: Review Exercises Chapter 1 Find an equation of the line having the given characteristics. Write the equation using the general form or the slope-intercept form, whichever you p

Algebra.Com
Question 158031This question is from textbook
: Review Exercises Chapter 1
Find an equation of the line having the given characteristics. Write the equation using the general form or the slope-intercept form, whichever you prefer. Graph each line.
9. Slope = -3; containing the point (2, -1)

y = -3x - 1 this is where I started
This question is from textbook

Answer by jim_thompson5910(35256)   (Show Source): You can put this solution on YOUR website!
First let's find the equation of the line

If you want to find the equation of line with a given a slope of which goes through the point (2,-1), you can simply use the point-slope formula to find the equation:


---Point-Slope Formula---

where is the slope, and is the given point


So lets use the Point-Slope Formula to find the equation of the line


Plug in , , and (these values are given)


Rewrite as


Distribute


Multiply and to get

Subtract 1 from both sides to isolate y


Combine like terms and to get


------------------------------------------------------------------------------------------------------------
Answer:


So the equation of the line with a slope of which goes through the point (2,-1) is:


which is now in form where the slope is and the y-intercept is



Since this tells us that the y-intercept is .Remember the y-intercept is the point where the graph intersects with the y-axis

So we have one point




Now since the slope is comprised of the "rise" over the "run" this means


Also, because the slope is , this means:




which shows us that the rise is -3 and the run is 1. This means that to go from point to point, we can go down 3 and over 1



So starting at , go down 3 units


and to the right 1 unit to get to the next point



Now draw a line through these points to graph

So this is the graph of through the points and


Also, notice how the graph has a slope of -3 (since ) and it goes through the point (2,-1).

RELATED QUESTIONS

find an equation of the line having the given characteristics X-intercept = 2; passing (answered by ankor@dixie-net.com)
The endpoints of the diameter of a circle are (-3,2) and (5,-6). Find the center and... (answered by bucky)
write an equation of the parabola with the given characteristics. vertex (0,0)... (answered by josgarithmetic)
find the slope-intercept equation of the line that has the given characteristics slope... (answered by josgarithmetic)
Review Questions: Given the following equation of a line, write an equation of a line... (answered by ikleyn,MathLover1)
Write an equation of an ellipse with the given characteristics: Center: (3,3)... (answered by robertb)
Write an equation of the hyperbola with the given characteristics. Foci: (-3,0),(3,0) (answered by Mathtut)
Find the slope-intercept equation of the line that has the given characteristics... (answered by stanbon)
Find the slope-intercept equation of the line that has the given characteristics... (answered by Fombitz)