SOLUTION: Graph -4x + 4y = -16.

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Question 125599: Graph -4x + 4y = -16.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: Graphing Linear Equations


-4%2Ax%2B4%2Ay=-16Start with the given equation



4%2Ay=-16%2B4%2Ax Add 4%2Ax to both sides

y=%281%2F4%29%28-16%2B4%2Ax%29 Multiply both sides by 1%2F4

y=%281%2F4%29%28-16%29-%281%2F4%29%28-4%29x%29 Distribute 1%2F4

y=-16%2F4%2B%284%2F4%29x Multiply

y=%284%2F4%29%2Ax-16%2F4 Rearrange the terms

y=1%2Ax-4 Reduce any fractions

So the equation is now in slope-intercept form (y=mx%2Bb) where m=1 (the slope) and b=-4 (the y-intercept)

So to graph this equation lets plug in some points

Plug in x=-5

y=1%2A%28-5%29-4

y=-5-4 Multiply

y=-9 Add

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





Now lets find another point

Plug in x=-4

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

y=-4-4 Multiply

y=-8 Add

So here's another point (-4,-8). Add this to our graph





Now draw a line through these points

So this is the graph of y=1%2Ax-4 through the points (-5,-9) and (-4,-8)


So from the graph we can see that the slope is 1%2F1 (which tells us that in order to go from point to point we have to start at one point and go up 1 units and to the right 1 units to get to the next point) the y-intercept is (0,-4)and the x-intercept is (4,0) . So all of this information verifies our graph.


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 1%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 up 1 units


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



Now draw a line through those points to graph y=1%2Ax-4


So this is the graph of y=1%2Ax-4 through the points (0,-4) and (1,-3)