8th grade math question, what is a easy way to do this?

Question

How can I find a easy way to know where the parentheses go in my math problems?
Im trying to find a easy way to learn this,

I need to put parentheses in the right place to make each statement true

1. 6-3to the 2nd powerx5-3= -42

2. 6-3to the 2nd powerx5-3= -18

3. 6- 3 to the 2nd powerx5-3= -36

4. 6-3 to the 2nd powerx5-3=-6

KenK · Accepted Answer

Try different combinations and see what you get.  For example, 
6-3to the 2nd powerx5-3
((6-3)^2)*(5-3) = (3*3)*2 = 18 (no match)
(((6-3)^2)*5)-3 = ((3*3)*5)-3 = 42 (no match)
Since these are all positive, you can give up on them.

6-((3^2)*5)-3 = 6-((3*3)*5)-3 = -42 (match!)

Wow, this is hard... are there other matches?!?

magget. (: · Answer

1. 6 - (3^2 x 5) - 3 = (-42) 

2. [(6 - 3^2) x 5] - 3 = (-18)

3. 6 - [(3^2 x 5) - 3] = (-36) 

4. (6 - 3^2) x (5 - 3) = (-6)

There's really no proper way to do this except for trial & error. You have to figure out different groupings and patterns for the numbers. And by the way, using just parentheses here isn't enough. You need to use brackets too to group numbers that are grouped with parentheses. (:

Trending News

8th grade math question, what is a easy way to do this?

2 Answers