i can`t figure this out?

Question

i know the square root of 81 is 9 but what is 72. Can you explain to me how to do it. I just failed my math test. plz

Answer 1

Here's a method for finding roots of numbers that aren't perfect squares:

http://www.math.com/school/subject1/lessons/S1U1L9DP.html

Answer 2

√81 = 9

√72 = √36 √2

6√2

Answer 3

The square root of 81 is 9, so 9 X 9 is 81. The square root of 64 is eight, so 8 X 8 is 64.

This means that the square root of 72 is a decimal number between 8 and 9.

To find it, you must square random decimals between 8 and 9 to find out the root of 72.

Answer 4

First off, √81 has *two* answers -9 and +9. You might lose points for that error. :)

For 72, the best you can do is reduce it, since it isn't a perfect square.

√72
= √(2 x 2 x 2 x 3 x 3)
= √(2 x 2) x √2 x √(3 x 3)
= 2 x √2 x 3
= 6√2

Using your calculator, you can get an approximation of:
≈ ±8.485281...

Don't forget the *two* answers (+ and -)!

Answer 5

It is known that 81 is the product of 9X9. Therefore we know that when 9 mutiply itself , the product is 81. In this case 9 is called the square root of 81. For 72, the square root is 6 times the sauqre root of 2.

Answer 6

There is no exact root of 72. What you can do, though, is simplify the root. Is there any perfect square number that 72 is divisible by (think 4, 9, 16, 25, 36..)? Yes. 72 is divisible by 36, so you can break it up into root(36*2), take the 36 out, and get 6root(2). Or, if you just want a decimal approximation, grab a calculator and punch it in.

Answer 7

Get a calculator that does square roots. It's between 8 and 9.

Answer 8

The answer is 8.4852813742385702928101323452582.

8.48... * 8.48... = 72.
9 * 9 = 81

A square root is a number which when multiplied by itself makes the original number.

ie. The square root of 25? 5 * 5 = 25, so it's 5.

Answer 9

Sq root of 72 is 8.485281...

Without a calculator, it's very hard to come up with an accurate answer.

Answer 10

It's 6 x sqr 2