SOLUTION: Please help me with this problem--- The graph of 3x - y + 6 crosses the x - axis at x = Thanking you

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Question 118726: Please help me with this problem---
The graph of 3x - y + 6 crosses the x - axis at x =
Thanking you
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
3x+-+y+%2B+6+=+0
3x+-+y+=+-6.........standard form...to find x, set y to 0
3x+-+0+=+-6.........
3x+=+-6.........
x+=+-6%2F3.........
x+=+-2.........

as you will see, the graph of 3x+-+y+%2B+6+=+0 crosses the x+-+axis at x+=-2


Solved by pluggable solver: Graphing Linear Equations


3%2Ax-1%2Ay=-6Start with the given equation



-1%2Ay=-6-3%2Ax Subtract 3%2Ax from both sides

y=%28-1%29%28-6-3%2Ax%29 Multiply both sides by -1

y=%28-1%29%28-6%29%2B%281%29%283%29x%29 Distribute -1

y=6%2B%283%29x Multiply

y=3%2Ax%2B6 Rearrange the terms

y=3%2Ax%2B6 Reduce any fractions

So the equation is now in slope-intercept form (y=mx%2Bb) where m=3 (the slope) and b=6 (the y-intercept)

So to graph this equation lets plug in some points

Plug in x=-5

y=3%2A%28-5%29%2B6

y=-15%2B6 Multiply

y=-9 Add

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





Now lets find another point

Plug in x=-4

y=3%2A%28-4%29%2B6

y=-12%2B6 Multiply

y=-6 Add

So here's another point (-4,-6). Add this to our graph





Now draw a line through these points

So this is the graph of y=3%2Ax%2B6 through the points (-5,-9) and (-4,-6)


So from the graph we can see that the slope is 3%2F1 (which tells us that in order to go from point to point we have to start at one point and go up 3 units and to the right 1 units to get to the next point) the y-intercept is (0,6)and the x-intercept is (-2,0) . So all of this information verifies our graph.


We could graph this equation another way. Since b=6 this tells us that the y-intercept (the point where the graph intersects with the y-axis) is (0,6).


So we have one point (0,6)






Now since the slope is 3%2F1, this means that in order to go from point to point we can use the slope to do so. So starting at (0,6), we can go up 3 units


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



Now draw a line through those points to graph y=3%2Ax%2B6


So this is the graph of y=3%2Ax%2B6 through the points (0,6) and (1,9)