How do you use the intercepts to graph #-x+4y=8#?

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Answer 1 · 2016-04-02T07:53:14

You only need two points to draw a line graph,therefore, compute the intercepts #(-8, 0)# and #(0, 2)# then connect the two points.

From the given equation #-x+4y=8#, just set one variable to zero at a time then solve for the numerical value of the other.

Let us do it

#-x+4y=8#

Set #y=0" "#and then substitute that value in the equation

#-x+4(0)=8#

#-x+0=8#

#-x=8#

#(-x)/(-1)=8/(-1)#

and

#x=-8#
this means there is a point on the line at #(-8, 0)#

Now set #x=0# and then substitute that value in the equation

#-(0)+4y=8#

#0+4y=8#

#4y=8#

#(4y)/4=8/4#

#y=2#

this means there is another point on the line at #(0, 2)#

Now, to graph the #-x+4y=8#, you only need to draw a line from #(-8, 0)# to #(0, 2)#

Kindly see the graph of #-x+4y=8# and check the two points we calculated.

graph{-x+4y=8[-20,20,-10,10]}

God bless...I hope the explanation is useful.