Question

Ashton estimates the square root of 72 in the following way: √72= 2√36=2×6=12 A)Explain why his reasoning is incorrect. B)Estimate the square root of 72 to the nearest tenth without using your calculator. Show your work.

Answer 1

8.5

Explanation:

To find √72, we must factor 72, remembering that the factor 36 is a perfect square:

√72 = √2·√36, or 6√2. Ashton failed to take the square root of the factor 2 of 72.

√72 = 6√2, and √2 is approx. 1.414.

Multiplying 1.414 by 6 results in 8.5, which is to the nearest tenth.