make y the subject please help
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Step-by-step explanation:
Square both sides and you will get
3xy/(x + y) = 4
Multiplying both by (x + y), we get
3xy = 4(x + y) = 4x + 4y
Put all the terms containing y to the left side:
3xy - 4y = 4x
y(3x - 4) = 4x
or y = 4x/(3x - 4)