mathematics

2. a quantity obtained by multiplying quantities together, or from an analogous algebraic operation.
4. a plane figure with four equal sides
5. a plane figure with three straight sides and three angles
7. linear distance around the outside of the closed curve or circular object
11. to take a number or a amount from another to calculate the difference
12. angle less than 90 degrees
14. a number by which another number is to be divided.
16. by adding the giving amount to another

1. a numerical quantity that is not a whole number
3. ascertain the size ,amount or degree of something by using an instrument
6. the measurement or extent of something from end to end;
8. triangle with two equal sides
9. round plane figure
10. a number of quantity that when multiplied with another produces a given number
13. the numerical value of the ratio of the circumference of a circle to its diameter
15. measure of the amount od space inside a sold figure