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17Simplifying root sums

Simplify √50 + √18 − √8, writing the answer in the form a√2.

Breaking each root into a perfect-square factor gives √50 = 5√2, √18 = 3√2, and √8 = 2√2. Adding and subtracting their coefficients, 5 + 3 − 2 = 6, so the answer is 6√2.

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