## Wednesday, 15 April 2015

### Real World Application of Algebra - Formulae

One of the Real World Applications of Algebra is FORMULAE.
Formulae (plural for formula) is often used to illustrate a relationship among factors (variables).

e.g. 1: Area of a rectangle
The formula illustrates a relationship between area, length and breadth
• Area of Rectangle = Length x Breadth
• When the length of the rectangle increases, the area of the rectangle also increases
• When the breadth of a rectangle decreases, the area of the rectangle also decreases

e.g. 2: Percentage change
The formula illustrates a relationship between percentage changes, the difference and the original amount
• Percentage change = ( Difference ÷ Original amount ) x 100%
• When the Difference between the original and new amount is large, the percentage change is large

You are going to...

In your group, look up for as many formula as you could and post them in the padlet designated to your group.

Instructions:
• One formula per post-it
• You need to tell us what does the formula do?
• Each formula exists for a purpose (to help us find out/ compute certain things)
• You may use keynote or Pages to present your answer. Save it as an image and post it in the padlet designated to your group.
• Complete this task by 18 March - Ready for discussion on Thursday (19 March)

Follow-up from lesson:

Instructions
Source: Textbook - Read p119 to p121

Attempt the following section in the AceLearning portal: Evaluation of Algebraic Expressions and Formulae to learn how the "substitution" is applied to find unknowns in various fields.
• In particular, examples 6 to 9