Year 10 Interactive Maths - Second Edition

The Algebraic Methods

Substitution Method

To solve the simultaneous equations, find the value of y in terms of x (or vice versa) for one of the two equations and then substitute this value into the other equation.

Example 2

Solve the following simultaneous equations by using the substitution method:

Solution:

Label the equations as follows:

So, the solution is (6, 9).

Note:

It is convenient to use the substitution method when one of the given equations has one of the variables as its subject.

Example 3

Solve the following simultaneous equations by using the substitution method:

Solution:

Label the equations as follows:

Key Terms

algebraic methods, substitution method

Study Another Topic in Chapter 4: Simultaneous Equations

[ Solution of Linear Simultaneous Equations ] [ The Algebraic Methods ] [ Elimination Method ] [ Problem Solving ] [ Problem Solving Unit ] [ Symbols ] [ Index ]