Writing an Inequapty Given a Graph on the Number Line

In this lesson, given a graph on the number pne, we write an inequapty for the graph.

Rules to write an inequapty given a graph on the number pne.

For any variable x

If the graph is a horizontal pne starting from a point ‘a’ with an open circle and an arrow towards left, it is a less than inequapty. x < a

If the graph is a horizontal pne starting from a point ‘a’ with a closed circle and an arrow towards left, it is a less than or equal to inequapty. x ≤ a

If the graph is a horizontal pne starting from a point ‘a’ with an open circle and an arrow towards right, it is a greater than inequapty. x > a

If the graph is a horizontal pne starting from a point ‘a’ with a closed circle and an arrow towards right, it is a greater than or equal to inequapty. x ≥ a

Write an inequapty for the graph on the number pne given below.

Solution

Step 1:

From the given graph on the number pne since the arrow is towards left and there is an open circle, it is a ‘less than’ inequapty.

Step 2:

Since it is starting from 190 with an open circle, the inequapty is x < 190

Write an inequapty for the graph on the number pne given below

Solution

Step 1:

From the given graph on the number pne since the arrow is towards left and there is a closed circle, it is ‘less than or equal to’ inequapty.

Step 2:

Since it is starting from −15 with a closed circle, the inequapty is x ≤ −15