First off, the underline underneath means plus or minus, since when you take the square root of something, the answer can be negative or positive at the same time
1. 64 is a perfect square. 8 x 8 = 64, therefore it is +- (plus or minus) 8.
2. 45 is not a perfect square, so you can pull out numbers or plug into a calculator and estimate.
Both answers: Since 45 is divisible by 9 and five, you can break a nine into two threes, therefore pull it out, and since the answer is negative, you get:
-3(5)^0.5 (an exponent of one-half or 0.5 means square root)
If you solve by calculator, the answer is ~= (approximately equal to) -6.72
3. Since 90 is not a perfect square, repeat the previous question. 9 can go into 90, therefore you can pull out two threes and are left with: +-3(10)^0.5
Using the calculator, you get ~= +-9.49
<em>The answer you are looking for is: </em>
<em><u>
270 
</u></em>
<em><u>15*18= 270 </u></em>
<em><u>And you have to add the yard square at the end. </u></em>
<em>Hope that helps!! </em>
<em>Have a wonderful day!!</em><span />
Answer:
1. 
2. 13.5 + 
3. 
6. 
These four options are rational;
Step-by-step explanation:
1. equals to 10 * 10 = 100 which is rational
2. 13.5 + equals 13.5 + 9 = 22.5
3. -- 3+27 = 30
6.
Option 4 and 5 are irrational because they include 
and 
which are not a perfect square and their answers will be non recurring and non terminating decimal fraction.
8 inches. 3/4 of 8 feet is 6 feet leaving two left over, one third of that is 8 inches.
