<s>[INST] Simultaneous equation with fractional solutions. How do you get to find $x$ when $y$ is a fraction ? Anyone mind to explain it step by step for the clearest explanation.=)
$$-7x +2y = 2$$
$$14x + 3y = -5$$
Answer: $x=?, y=-1/7$ 
 [/INST] The correct solution to your system of equations is $y = -\frac{1}{7}$ and you want to find $x$. To do so, substitute this value of $y$ into the first equation to get $$-7x - 2\cdot \frac{1}{7} = 2 \iff -7x = \frac{16}{7} \iff x = -\frac{16}{49}$$ by re-arranging and solving for $x$.
Alternatively, you could substitute your $y$ value into the second equation to get $$14x - 3\cdot \frac{1}{7} = -5 \iff 14x = -\frac{32}{7} \iff x = -\frac{16}{49}$$ by re-arranging and solving for $x$.
So the solution to your system of equations is $x = -\frac{16}{49}, y = -\frac{1}{7}$. 
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