Title: Lesson 11-2
Author: mark_cameron
Last saved by: Unknown User
Company: McGraw-Hill

Lesson 13-1

Example 1  Estimate a Square Root
Estimate √30 to the nearest whole number.

List some perfect squares.
1, 4, 9, 16, 25, 36, …

	25 <	30	<	36	30 is between the perfect squares 25 and 36.
	√25 < √30 < √36	Find the square root of each number.
	5 <	 √30 < 6	√25 = 5 and √36 = 6

So, √30 is between 5 and 6. Since 30 is closer to 25 than to 36, the best whole number estimate is 5. Verify with a calculator

Example 2  Use a Calculator to Estimate
Use a calculator to find the value of √55 to the nearest tenth.

√55 = 7.416198487

√55 ≈ 7.4

Check  7^2 = 49 and 8^2 = 64. Since 55 is between 49 and 64, the answer, 7.4, is reasonable.