Introduction

This is an introduction to solving simultaneous equations by the method of elimination.

x terms are the same

In the next example only the x terms are the same.

Example in the video

Solve the simultaneous equations:

1. 2x + 3y = 7
2x + y = 5

y terms the same but with opposite signs

In this example the two equations have the same y terms but with opposite signs.

Care must be taken over the signs as mistakes can easily be made.

Example in the video

Solve the simultaneous equations:

1. 3x – 2y = 7
5x + 2y = 17

y terms are the same and both signs are negative

In this example the y terms are exactly the same and both signs are negative.

Care must be taken over the signs as mistakes can easily be made.

Example in the video

Solve the simultaneous equations:

1. 4x – 3y = 6
2x – 3y = 0

y terms are the same and both signs are positive

In this example the y terms are exactly the same and both signs are positive.

Example in the video

Solve the simultaneous equations:

1. 5x + 4y = 13
x + 4y = 9

Neither the x or y terms are the same

In this example neither the x or y terms are the same so an adjustment needs to be made.

Example in the video

Solve the simultaneous equations:

1. 7x – 2y = 22
5x + 3y = 29