Answer: Choice B) 9/10
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Work Shown:
![\sqrt{(81)/(100)}\\\\\\(√(81))/(√(100))\\\\\\(√(9^2))/(√(10^2))\\\\\\(9)/(10)\\\\\\](https://img.qammunity.org/2023/formulas/mathematics/high-school/vq6646stzxtz39g5e0kw2g349j4npu9ljr.png)
Therefore,
![\sqrt{(81)/(100)}=(9)/(10)\\\\\\](https://img.qammunity.org/2023/formulas/mathematics/high-school/mo9j1x892iuzlqwvnsdyqtwyub2ajt71rr.png)
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Explanation:
I broke up the single square root to make a fraction of square roots. Then I rewrote 81 as 9^2, and 100 as 10^2. This is so the square roots cancel out with the squares.
The general rule is that
![\sqrt{\text{x}^2} = \text{x} \ \text{ , where x} \ge 0](https://img.qammunity.org/2023/formulas/mathematics/high-school/br5hb9x7l0jzuzci0cex0v5qj240atlqkz.png)