**
10). (3 points) ****What is the length of one side of a square whose area is 81 square inches?** Side = __________

11). (3 points) **The equation for the area of a circle is: **

A = R R

Rewrite this equation using the square symbol. A = _________________________

12). (3 points) **The area of a square is .4096 square feet. What is the length of one of its sides?** Side = __________

13). (3 points) **I am thinking of a number. If you square my number and then add 5 you get 54. What is my number?** Equation:_____________________

Answer:_______________

14). (3 points)[Extra Credit]

**Do this on your calculator:**

- Compute 4 - 8 (answer should be -4)
- Hit the "" key (takes square root of -4)

What happened?

Why?