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catlover
05-15-2009, 02:53 PM
-2(15/-5)-6/2+9

-Knight-
05-15-2009, 03:27 PM
Just use the order of operations to do out the problem.

-2(15/-5)-6/2+9

you start with executing any parenthesis

-2(-3)-6/2+9

You then do exponents. but their are none.

-2(-3)-6/2+9

You then do multiplication and division. starting from left to right. (multiplication and division are "equal" in the order of operations)

-2(-3) = 6

-6/2 = -3

plug in those values...

6-3+9

You then do addition and subtraction at the same time. starting from left to right. (same deal here as above)

I will leave the last step to you :)

A shortcut to remember order of operations is PEMDAS

P:parentheses 1
E:exponents 2
M:multiplication 3
D:division 3
A:addition 4
S: subtraction 4

The numbers represent in what order to use the operations
Knight

Subhotosh Khan
05-15-2009, 07:58 PM
Just use the order of operations to do out the problem.

-2(15/-5)-6/2+9

you start with executing any parenthesis

-2(-3)-6/2+9

You then do exponents. but their are none.

-2(-3)-6/2+9

You then do multiplication and division. starting from left to right. (multiplication and division are "equal" in the order of operations)

-2(-3) = -6 <<< Incorrect -2(-3) = (+)6

-6/2 = -3

plug in those values...

-6-3+9

You then do addition and subtraction at the same time. starting from left to right. (same deal here as above)

I will leave the last step to you :)

A shortcut to remember order of operations is PEMDAS

P:parentheses 1
E:exponents 2
M:multiplication 3
D:division 3
A:addition 4
S: subtraction 4

The numbers represent in what order to use the operations
Knight

-Knight-
05-15-2009, 11:14 PM
post edited. thanks :)

Denis
05-15-2009, 11:38 PM
-2(15/-5)-6/2+9
BEFORE doing anything, helps if you rewrite it this way: 9 - 6/2 - 2(15/-5) .
But that's me!

Petenerd
05-16-2009, 01:55 PM
First do 15/-5, which is -3. Then take -2 *-3, which is 6. This is how it should look so far, 6-6/2+9. 6/2, 3. Then 6-3+9. 6-3=3. 3+9=12.