Unit 2 Math Review

Prime numbers have ONLY 2 factors--1 and the number itself. Example: 17 is prime because ONLY 1 x 17 = 17.

SOME odd numbers are prime.

2 is is the ONLY EVEN prime number.

Composite numbers have MORE THAN 2 factors. Example: 12 is composite because 12 x 1, 2 x 6, and 3 x 4 = 12.

ALL even numbers except 2 are composite.

SOME odd numbers are composite.

To find the right equation, focus on the KEY words in the problem. Think about the operation you need and what the KEY words and NUMBERS are telling you. Draw a picture/diagram if needed.

The VARIABLE will NEVER be ALONE!

5 + b = 10 (YES)

10-5 = b (NO)