Back to Course

JSS2: MATHEMATICS - 3RD TERM

0% Complete
0/0 Steps
  1. Expansion and Factorization of Algebraic Expressions | Week 1
    4Topics
    |
    1 Quiz
  2. Algebraic Expansion and Factorization of Algebraic Expression | Week 2
    4Topics
    |
    1 Quiz
  3. Algebraic Fractions I | Week 3
    4Topics
    |
    1 Quiz
  4. Addition and Subtraction of Algebraic Fractions | Week 4
    2Topics
    |
    1 Quiz
  5. Solving Simple Equations | Week 5
    4Topics
    |
    1 Quiz
  6. Linear Inequalities I | Week 6
    4Topics
    |
    1 Quiz
  7. Linear Inequalities II | Week 7
    2Topics
    |
    1 Quiz
  8. Transactions in the Homes and Offices | Week 8
    5Topics
    |
    1 Quiz
  9. Quadrilaterals | Week 9
    2Topics
    |
    1 Quiz
  10. Angles in a Polygon | Week 10
Lesson 7, Topic 2
In Progress

Words Problems Leading to Inequalities

Lesson Progress
0% Complete

Example 1

If x is subtracted from 5 and the result is greater than 15. Find the range of values of x

Solution 

x subtracted from 5

5 – x

Result > 15

\( \scriptsize 5 \: – \: x > 15 \)

Collect like terms

\( \scriptsize 5 \: – \: x > 15 \)

\( \scriptsize -x > 15 \: – \: 5 \)

\( \scriptsize -x > 10 \)

Divide both sides by -1 (reverse the sign) 

\( \frac {-x}{-1} < \frac{10}{-1} \)

\( \scriptsize x < -10 \)

Range of values of x :  -11, -12, -13, … 

Example 2 

Olu is x years old. In 4 years time his age will still be less than 12 years. 

(a) Write this information in an inequality in x

(b) Find the maximum age of Olu to the nearest whole number 

Solution 

(a) In 4 years time, Olu will be (x + 4) years 

x + 4 is less than 12 

\( \scriptsize x \: + \: 4 < 12 \)

(b) Solve \( \scriptsize x \: + \: 4 < 12 \)

collect like terms

\( \scriptsize x < 12 \: – \: 4 \)

\( \scriptsize x < 8\)

Range of values of x:  7, 6, 5, 4, 3, …

Maximum age of Olu is 7 years 

Responses

Your email address will not be published. Required fields are marked *

back-to-top
error: