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Question
Solve Y=1/3X-5 X-y/5=13
thx
Putting the 1st equation into the 2nd equation gives x - (x/3 - 5)/5 = 13.
That is, (1 - 1/15)x + 1 = 13, which goes to 14x/15 = 12, so x = (15/14)12 = 90/7.
Looking at the 2nd equation, this says that 90/7 - y/5 = 13.
Since 13 = 91/7, subtracting 90/7 from both sides leaves -y/5 = 1/7.
This means y = -5/7.
Puttiing both values in the 1st equation to check gives -5/7 = (90/7)/3 - 5.
Since 5 = 35/7, that can be changed to -5/7 = 30/7 - 35/7.
This is true, since -5 = 30 - 35.
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| Rating(1-10) | Knowledgeability = 10 | Clarity of Response = 10 | Politeness = 10 |
| Comment | Very prompt and well illustrated Thanks again | ||
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Scott A Wilson
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Any algebraic question you've got, like linear, quadratic, exponential, etc.
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