# Graphs of Simple Function

Here we will learn about the graphs of simple functions that is multiples of different numbers.

The example will help us to understand the graph of multiples of different numbers.

1. Draw the graph of the function y = 3x.

2. From the graph, find the value of y, when

(a) x = 4

(b) x = 5

Solution:

1. The given function is y = 3x.
For some different values of x, the corresponding values of y are given below.

         x 0 1 2 3 y = 3x 0 3 6 9

On a graph paper plot the points O (0, 0), A (1, 3), B (2, 6) and C (3, 9) and join them successively to obtain the required graph.

2. Reading off from the graph of simple function:

(a) On the x-axis, take the point L at x = 4.

Draw LP ⊥ x-axis, meeting the graph at P.

Clearly, PL = 12 units.

Therefore, x = 4 ⇒ y = 12.

(b) On the x-axis, take the point M at x = 5.

Draw MQ ⊥ x-axis, meeting the graph at Q.

Clearly MQ = 15 units

Therefore, x = 5 ⇒ y = 15

Related Concepts:

Coordinate Graph

Signs of Coordinates

Find the Coordinates of a Point

Coordinates of a Point in a Plane

Plot Points on Co-ordinate Graph

Graph of Linear Equation

Simultaneous Equations Graphically

Graph of Perimeter vs. Length of the Side of a Square

Graph of Area vs. Side of a Square

Graph of Simple Interest vs. Number of Years

Graph of Distance vs. Time