Simultaneous equations
Learn the method, practise it, then try real exam questions.
ATeaching
Example 1
Solve x + 3y = 142x + y = 13
- 1Choose a letter to eliminate (here x). Multiply the top equation by 2 to make the x terms the same:
- 2Write the new top equation above the bottom equation. The signs are the same, so subtract:
- 3Divide both sides by 5 to find y:
y = 15 ÷ 5
y = 3 - 4Substitute y = 3 into the top equation from the start:
x = 5 and y = 3
Example 2
Solve 2x + 3y = 123x − 2y = 5
- 1Choose a letter to eliminate (here y). Multiply the top equation by 2 and the bottom equation by 3 to make the y terms the same size:
- 2Write the new equations. The signs are different, so add:
- 3Divide both sides by 13 to find x:
x = 39 ÷ 13
x = 3 - 4Substitute x = 3 into the top equation from the start:
x = 3 and y = 2
BQuestion generator
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CWorksheet
Simultaneous equations
6 pairs of simultaneous equations questions. 2 have no change, 2 where one equation needs to change and 2 where both equations need to change.
DPast exam questions
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