Draw the graph of the equation 2x - 3y = 5. From the graph, find (i) the value of y when x = 4, and (ii) the value of x when y = 3.

The given equation is, 2x - 3y = 5


y =


Now, if x = 4, then


y = = = 1


And, if x = -2, then


y = = = -3


Thus, we have the following table:


x



4



-2



y



1



-3



Plot points (4,1) and (-2,-3) on a graph paper and join them to get the required graph.



(i) When x = 4, draw a line parallel to y-axis at a distance of 4 units from y-axis to its right cutting the line at Q and through Q draw a line parallel to x-axis cutting y-axis which is found to be at a distance of 1 units above x-axis.


Thus, y = 1 when x = 4.


(ii) When y = 3, draw a line parallel to x-axis at a distance of 3 units from x-axis and above it, cutting the line at point P. Through P, draw a line parallel to y-axis meeting x-axis at a point which is found be 7 units to the right of y axis.


Thus, when y = 3, x = 7.


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