Algebra: Using the Order of Operations - PEMDAS - When to do what?

1 - First you have to have an understanding of the rules of algebra .
2 - Order of Operations is PEMDAS. Parenthesis, exponents, multiplication, division, addition and subtraction.
3 - Know your math facts!
4 - Neatness counts!
5 - Follow a pattern to your work. See below

(a) 3.5 *2 + x^0 - (3+7) /2  =  3.5 *2 + x^0 - 10/2 --- rule --->  parentheses
(b) 3.5 *2 + x^0 - 10/2  = 3.5 *2 + 1 - 10/2 --- rule ---> exponents (x^0 means x to the zeroth power)
(c) 3.5 *2 + 1 - 10/2  = 7 + 1 - 10/2  --- rule ---> multiplication
(d) 7 + 1 - 10/2 = 7 + 1 -5 --- rule ---> multiplication table
(e) 7 + 1 -5 = 8 - 5 --- rule---> addition fact table
(f) 8 - 5 = 3  --- rule ---> subtraction fact table