Algebra (Equations

and inequalities)

3

Contents:

A Solving linear equations [2.3]

B Solving equations with fractions [2.3]

C Forming equations

D Problem solving using equations

E

F Interpreting linear inequalities [2.1]

G Solving linear inequalities [2.2]

Opening problem

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Dinesh has an older brother named Mandar who weighs

87 kg, and a younger brother named Ravi who weighs

63 kg. Dinesh is heavier than Ravi, but lighter than

Mandar.

Suppose Dinesh weighswkilograms.

Can you represent the possible values forwusing an

inequality?

Many problems in mathematics can be solved by usingequations. We convert the worded problem into an

algebraic equation by representing an unknown quantity with a variable such asx. We then follow a formal

procedure tosolvethe equation, and hence find the solution to the problem.

Alinear equationis an equation which contains a variable which is not raised to any power other than 1.

For example, 3 x+4=2,^23 x+1=6, and

x¡ 1

4

=8 are all linear equations.

In this section we review the formal procedure for solving linear equations.

A SOLVING LINEAR EQUATIONS [2.3]

Power equations

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