SOLUTION: graph the functions. f (x)=2x - 5

Algebra ->  Graphs -> SOLUTION: graph the functions. f (x)=2x - 5       Log On


   

Question 91395: graph the functions.
f (x)=2x - 5

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-5 we only need to plug in two points to draw the line

So lets plug in some points

Plug in x=-2

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

y=-4-5 Multiply

y=-9 Add

So here's one point (-2,-9)




Now lets find another point

Plug in x=-1

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

y=-2-5 Multiply

y=-7 Add

So here's another point (-1,-7). Add this to our graph





Now draw a line through these points

So this is the graph of y=2%2Ax-5 through the points (-2,-9) and (-1,-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 up 2 units and to the right 1 units to get to the next point) the y-intercept is (0,-5)and the x-intercept is (2.5,0) ,or (5%2F2,0)


We could graph this equation another way. Since b=-5 this tells us that the y-intercept (the point where the graph intersects with the y-axis) is (0,-5).


So we have one point (0,-5)





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,-5), we can go up 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-5


So this is the graph of y=2%2Ax-5 through the points (0,-5) and (1,-3)