Draw the graph (straight line) given by equation x - 3y = 18. If the straight line drawn passes through the points (m, -5) and (6, n); find the values of m and n.

Given equation: x - 3y = 18

Step 1:

Give at least three suitable values to the variable x and find the corresponding values of y.

Let x = 0, then 0 - 3y = 18 ⇒ y = - 6

Let x = 3, then 3 - 3y = 18 ⇒ y = - 5

Let x = 6, then 6 - 3y = 18 ⇒ y = - 4

Step 2:

Make a table (as given below) for the different pairs of the values of x and y:

Step 3:

Plot the points, from the table, on a graph paper and then draw a straight line passing through the points plotted on the graph.

Since, point (m, -5) lies on the straight line drawn, through y = -5, draw a horizontal line which meets the graph at a point, say P. Through P, draw a vertical line which meets the x-axis at x = 3.

Also, (6, n) also lies on the straight line drawn, through x = 6, draw a vertical line which meets the graph at a point, say Q. Through Q, draw a horizontal line which meets the y-axis at x = -4.

Hence, m = 3 and n = -4.