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[quote=Anonymous]To simplify math expressions, use the acronym PEMDAS, working from left to right within both the acronym and the problem. This tells you the order in which you do each step to simplify the problem.

[b]P[/b]arentheses, [b]E[/b]xponents, [b]M[/b]ultiplication, [b] D[/b]ivision, [b]A[/b]ddition, [b]S[/b]ubtraction

Multiplication and division have equal precedence, so if both multiplication and division are present in the problem you simply work your way across the problem from left to right. Do not automatically do multiplication first if division comes first in the problem. For example:30 ÷ 5 × 3 =6 × 3= 18 is correct, but 30 ÷ 5 × 3=30 ÷ 15=2 is wrong.
 
Similarly, once you have reached the last two letters in the acronym, addition and subtraction have equal precedence. If both addition and subtraction are present, do them in the order they appear from left to right.

[b][u] Problem #1: 6^2 - 4* (7-4) [/b][/u]

First do what is in the Parenthases: 6^2 - 4* (7-4) --&gt; 6^2 - 4* (3)  because 7-4=3, so you simplify that part.
Second, do Exponents: 6^2 - 4* (3) --&gt; 36 - 4*(3) because 6^2 = 36.
Third, do Multiplication: 36 - 4*(3) --&gt; 36 - 12 because 4*3=12. 4*3 and 4*(3) and 4(3) are all ways of writing out the same multiplication problem and they are equivalent to each other.
There is no Division or Addition, so simply solve the remaining problem. 36 - 12 = [b]24[/b]

6^2 - 4* (7-4)
6^2 - 4* (3)
36 - 4*(3)
36 – 12 =24
The answer to problem #1 is 24.

[b][u] Problem #2: 5^2 - 4* (5-3) [/b][/u]
Use the same process as above. 
First do what is in the Parenthases: 5^2 - 4* (5-3) --&gt; 5^2 - 4* (2)
Second, do Exponents: 5^2 - 4* (2) --&gt; 25 - 4*(2)
Third, do Multiplication: 25 - 4*(2) --&gt; 25 - 8
There is no Division or Addition, so simply solve the remaining problem. 25 - 8 = [b]17[/b]

5^2 - 4* (5-3)
5^2 - 4* (2)
25 - 4*(2)
25 - 8 = 17
The answer to problem #2 is 17, or c. 
[/quote]

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