Question

Draw the graph of the equation x + 2y - 3 = 0.

From your graph, find the value of y when (i) x = 5 (ii) x = - 5.

Answer 1

The given equation is x + 2y – 3 = 0.

Assuming the values for any one variable, we can get the value for the other.

Thus, assuming the values of y as -2 and 2 we get:

y = -2⇒ x = 3 – 2(-2) = 7

y = 2 ⇒ x = 3 – 2(2) = -1

Forming the table:

x	7	-1
y	-2	2

Plotting the points on the graph sheet, we obtain the required graph:

Take a point P on x-axis such that OP = 5

Draw PQ parallel to y-axis cutting the line x = 3 – 2y at Q. Through Q, draw PN parallel to x-axis onto y-axis . Hence, y = ON = -1

now take on other side of x-axis such that x=-5

following the same procedure, we get y =13