The given equation is 2log3 y + log3 x2 = 4.
We can simplify this equation using the laws of logarithms. First, we can use the power rule of logarithms to rewrite x2 as (x)2. Then, we can use the product rule of logarithms to combine the two logarithms on the left-hand side of the equation:
2log3 y + log3 (x)2 = log3 y2 + log3 (x)2
Now, we can use the sum rule of logarithms to combine the two logarithms on the right-hand side of the equation:
log3 y2(x)2 = log3 (x2y2)
We can now rewrite the original equation as:
log3 (x2y2) = 4
Using the definition of logarithms, we know that log3 (x2y2) = 4 is equivalent to 3^4 = x2y2. Therefore, we have:
x2y2 = 81
Taking the square root of both sides, we get:
xy = ±9
Since y is a positive real number, we can discard the negative solution. Therefore, we have:
xy = 9
Finally, we can solve for y:
y = 9/x
So, the answer is "±9/x".