SOLUTION: Graph the following linear equation: y=-2x-1 Any help with this one would be great. Thank you so much.

Algebra ->  Linear-equations -> SOLUTION: Graph the following linear equation: y=-2x-1 Any help with this one would be great. Thank you so much.      Log On


   

Question 102647: Graph the following linear equation:
y=-2x-1

Any help with this one would be great. Thank you so much.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: Graphing Linear Equations
In order to graph y=-2%2Ax-1 we only need to plug in two points to draw the line

So lets plug in some points

Plug in x=-5

y=-2%2A%28-5%29-1

y=10-1 Multiply

y=9 Add

So here's one point (-5,9)




Now lets find another point

Plug in x=-4

y=-2%2A%28-4%29-1

y=8-1 Multiply

y=7 Add

So here's another point (-4,7). Add this to our graph





Now draw a line through these points

So this is the graph of y=-2%2Ax-1 through the points (-5,9) and (-4,7)


So from the graph we can see that the slope is -2%2F1 (which tells us that in order to go from point to point we have to start at one point and go down -2 units and to the right 1 units to get to the next point), the y-intercept is (0,-1)and the x-intercept is (-0.5,0) ,or (-1%2F2,0)


We could graph this equation another way. Since b=-1 this tells us that the y-intercept (the point where the graph intersects with the y-axis) is (0,-1).


So we have one point (0,-1)





Now since the slope is -2%2F1, this means that in order to go from point to point we can use the slope to do so. So starting at (0,-1), we can go down 2 units



and to the right 1 units to get to our next point


Now draw a line through those points to graph y=-2%2Ax-1


So this is the graph of y=-2%2Ax-1 through the points (0,-1) and (1,-3)