- Prime factorize 180 to find the largest perfect square factor: \(180 = 36 \times 5\).
- Apply the radical property \(\sqrt{a \cdot b} = \sqrt{a} \cdot \sqrt{b}\) to isolate the square root: \(\sqrt{36 \cdot 5} = \sqrt{36} \cdot \sqrt{5}\).
- Simplify the expression: \(6\sqrt{5}\).
- Match the result to the options provided: \(\boxed{\text{(A)}}\).
Explanation
- Factorizing 180
To simplify the radical \(\sqrt{180}\), we aim to express the number under the square root, 180, as a product of a perfect square and another factor. This allows us to use the property \(\sqrt{x \cdot y} = \sqrt{x} \cdot \sqrt{y}\). First, we perform prime factorization of 180:
\[180 = 18 \times 10 = (2 \times 9) \times (2 \times 5) = 2 \times 3^2 \times 2 \times 5 = 2^2 \times 3^2 \times 5 = 4 \times 9 \times 5 = 36 \times 5.\]
We identify 36 as the largest perfect square factor.
- Simplifying the Radical
Using the property \(\sqrt{x \cdot y} = \sqrt{x} \cdot \sqrt{y}\), we can rewrite the expression:
\[\sqrt{180} = \sqrt{36 \times 5} = \sqrt{36} \cdot \sqrt{5}.\]
Since the square root of 36 is 6, we have:
\[\sqrt{36} \cdot \sqrt{5} = 6\sqrt{5}.\]
Thus, the simplified form of \(\sqrt{180}\) is \(6\sqrt{5}\).
- Evaluating the Choices
Now we compare our result with the given choices:
A\(6\sqrt{5}\)
B\(9\sqrt{20}\)
C\(2\sqrt{90}\)
D\(18\sqrt{10}\)
We have already found that \(\sqrt{180} = 6\sqrt{5}\), which matches option (A). We can verify the others:
- (B) \(9\sqrt{20} = \sqrt{81 \times 20} = \sqrt{1620}\)
- (C) \(2\sqrt{90} = \sqrt{4 \times 90} = \sqrt{360}\)
- (D) \(18\sqrt{10} = \sqrt{324 \times 10} = \sqrt{3240}\)
None of these are equal to \(\sqrt{180}\). Therefore, the correct choice is (A).
Examples
Simplifying radicals is essential in many fields, including architecture and construction. For instance, if you need to calculate the length of a diagonal in a rectangular garden measuring \(\sqrt{180}\) units, you can use the simplified form to make measurements much more manageable. Instead of working with an unwieldy number, you can express it as \(6\sqrt{5}\), which helps you estimate or calculate precise dimensions more easily in your projects.