Answer:
10 Liters of 40% solution
Step-by-step explanation:
Answer: 
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Work Shown:

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Explanation:
The idea is to first get all the y terms to one side. I did this by subtracting 2y from both sides in the third step.
Then factor out y and divide both sides by (8x-2)
Afterward there's the optional steps of simplifying (as shown in the final two steps).
Answer:
3x²+8xy+4y²
Step-by-step explanation:
Opening brackets,
3x²+6xy+2xy+4y²
=3x²+8xy+4y²
669.949 should be your result hope it helps and ask me anything you didn’t understand!