 # Square Root Expression

Directions: Using the digits 1 to 9, at most one time each, fill in the boxes to make the following expression as close to 0 as possible. ### Hint

What are all the perfect square three digit numbers? Several of these can’t be used since they contain a repeated digit (e.g. 121 uses the digit 1 twice and 144 uses the digit 4 twice)

Using Perfect squares:
Sqrt(256) – sqrt(81) – sqrt(9) = 4

Using non-perfect squares:
Sqrt(145) – sqrt(92) – sqrt(6) = 0.00044178938368

Source: Erick Lee

## Systems of Equations 1

Directions: Using the integers -9 to 9 at most one time each, fill in the …

1. Dang it.

I got:
√124 – √89 – √3 = -0.030503214

• You tried. That is what is important!

• Good job!! It doesn’t matter if you make a mistake! The important thing is that you tried! You did your personal best and that is what matters!!! Just keep trying and you will make a good answer eventually!! Just do your personal best and if you get it wrong than don’t worry about it! it is fine! Keep on trying!

• The 4 closest answers are 138, 95, 4
124 69 8
132 75 8
145 92 6
But 124 69 8 is the most epik because 69

2. Should it not be √256 – √81 -√49 = 0 ?

• Your answer looks correct. Maybe the wording needs to be clarified? It says as close to zero, maybe the question needs to state without equaling zero?

• The last term has space for only one digit, so √49 doesn’t work.

• I thought there could only be one digit square root on the last term?

• Correct Kathy and Suzanne. Unfortunately Kristen, the last root must have a single digit.

3. 4. √121-√81-√4
The answer to this equation would be 0

• You can only use the digit “1” at most once.

5. or 11-9-2 when It is simplified

6. or √121-√64-√9
The answer would be 0 as well

7. you are repeating the number 1 , 121 has two and then theres a third “1” in 81

8. /121-/64-/9=0

9. Abbey Turrentine

257-81-49=4

10. 11. |121|-|81|-|4|

12. |121|-|81|-|5|

13. |121|-|82|-|5|

14. Spencer Turrentine

121-81-9= 4

15. I was working on this problem in preparation for having my 8th grade students work on it. I assumed that I should place digits so that the digits under each radical formed a perfect square, but then I realized the directions didn’t explicitly state that. I am interested in hearing how teachers have used this problem in their classroom and the discussions that resulted.

16. So far I have √105 – √68 – √4 = .00073951472

• Update: I got √140 – √9 – √78 = 0.00039869987