Question 1113189
d, dooughnut price
c, coffee price


{{{system(3d+6c=6.27,2d+3c=3.4)}}}

You can try the Elimination Method.
Easiest to first eliminate c and find d.
Multiply the second equation by 2...


{{{system(3d+6c=6.27,4d+6c=6.8)}}}


Subtract first of these from the second of these:
{{{(4d+6c)-(3d+6c)=6.8-6.27}}}

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