SOLUTION: Graph f(x) = –2x + 4.

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Question 112836: Graph f(x) = –2x + 4.
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%2B4 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%2B4

y=4%2B4 Multiply

y=8 Add

So here's one point (-2,8)




Now lets find another point

Plug in x=-1

y=-2%2A%28-1%29%2B4

y=2%2B4 Multiply

y=6 Add

So here's another point (-1,6). Add this to our graph





Now draw a line through these points

So this is the graph of y=-2%2Ax%2B4 through the points (-2,8) and (-1,6)


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 (0,4)and the x-intercept is (2,0)


We could graph this equation another way. Since b=4 this tells us that the y-intercept (the point where the graph intersects with the y-axis) is (0,4).


So we have one point (0,4)





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 (0,4), 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%2B4


So this is the graph of y=-2%2Ax%2B4 through the points (0,4) and (1,2)