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maths_header

 

 

Unit 7.2: The Addition and subtraction method.

In this section we actually get down to solving the simultaneous equations that we formed in the previous section.
Our first example in the previous section had


When do we know whether to add or subtract? Well, just follow the golden rule:
If the coefficients and signs are the same we should subtract. (otherwise add).

 

Hence, suppose we take route (a)..