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CHAPTER 3.1
In this chapter
Pupiis should be able to:
• construct simple
algebraic expressions by
using letters to represent
numbers
• know the meanings
of the words term, In Stage 1, we used symbols such as A or □ to stand for a number.
expression and equation
• simplify linear expressions
by collecting like terms Investigate!
\
• expand linear expressions
by multiplying a constant What are the possible pairs of numbers that could make 10? In other
over a bracket words, what number can each symbol stand for?
• know that algebraic
operations follow the = 10
same order as arithmetic □•o-
operations
We are looking for possible answers to satisfy the sentence. We can list the
number pairs to 10. We can also use a table to help us.
□ •
^ RECALL 1 9
2 8
What number does each 3 7
symbol stand for?
4 6
O; There are many possible solutions to the mathematical sentence. Instead of
using symbols in the sentence, we can use letters x and y.
We can write x + y = 10. We see that the values of x and the values for y
can vary.
X can be 1 and y can be 9, or x = 3 and y = 7.
We say that x and y are solutions to the problem.
x + y is an algebraic expression.x + y = 10 is an equation.
10
An expression is used to represent a value in algebraic form. It is different
from an equation. An equation contains an equal sign {=) which shows that
the expressions on either side of it are equal to each other.
-• Think and Share
Can you list all the pairs of solutions to the problem in above?
Introduction to Algebra and Equations
