Question 6406
3y=3x-6
9=8x-9y
<P>
In standard form,
3y=3x-6...[1]
9y=8x-9...[2]
<P>
Plot the first line on a graph,and then plot the second.The point of intersection of the two straight lines is the unique solution of the two equations.
<P>
Note:if you solved these two equations using algebra,you would get:
(x=9, y=7}
<P>However,as you are graphing these two points,we get-
[1st line]{Simplifying:y=x-2}
<font color=blue>x,y</font>
7,5
9,7
11,9
<br>
[2nd line]{Simplifying:y=(9-8x)/-9}
<font color=blue>x,y</font>
7,47/9
9,7
11,79/9
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Since this might not be all that clear,I am including the graph as well.
It should look something like this:<br>
{{{ graph( 650, 450, -5, 12, -5, 12, x-2, ((9-8x)/-9)) }}}
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<font color=blue>As you can see from the above graph,the point of intersection is (9,7) and hence this is the solution for the given pair of equations.</font><P>Prabhat.