<span><u><em>Answer:</em></u> either y = 4.5 or y = -4.5
<u><em>Explanation:</em></u> To get the solution, we will need to isolate the y on one side of the equation. <u>This can be done as follows:</u> 4y</span>²<span> = 81
</span> <span> y</span>²<span> = 20.25
y = +/- </span>√(20.25)<span> either y = +</span>√<span>(20.25) = 4.5 or y = -</span>√<span>(20.25) = -4.5
Since there are no restrictions on the value of y, therefore, both answers would be accepted