Name ___________________________________
Date __________________
Mr. Tallman
Math 8R
Do Now
Evaluate the following without a calculator:
1) √25 =
2) √49 =
5) 82 =
6) 122 =
3) √100 =
4) √121=
7) 42 =
8) 62 =
Lesson #4 – Approximating Square Roots to the Nearest Whole Number
Recall the first 15 perfect squares:
12 =
22 =
32 =
42 =
52 =
62 =
72 =
82 =
92 =
102 =
112 =
122 =
132 =
142 =
152 =
Evaluate the following square roots:
1) √169 =
2) √225 =
3) −√64 =
Example 1) Evaluate √10 to the nearest whole number.
Steps to approximating non-perfect squares to the nearest whole number:
Steps
1) Determine which two perfect squares √10 falls
between.
2) Of those two perfect squares, determine if √10 is
closer to the lower perfect square or the higher
perfect square.
3) Evaluate the square root of either the lower
perfect square or the higher perfect square.
4) Write your answer.
Example
Example 2) Approximate √34 to the nearest whole number.
Example 3) Approximate √28 to the nearest whole number.
Example 4) √40 is between what two integers?
Now, You Try!
Approximate the following square roots to the nearest whole number.
5) √85
6) √6
8) √8 is in between which two integers?
9) √50 is in between which two integers?
7) √117