Any 6th grade math teachers out there? Or anyone who "gets" math?

[kristilew]

So DD gets these Week By Week math sheets regularly for homework. We both hate them. Neither one of us is a math thinker, and since they are not related to what she is doing in class, we can't look in a book or reference her notes to try to figure out how to solve them.

I finally gave up and found the answer key online and saved it to reference. (No, I don't give her the answers, but I have no idea if her answers are correct otherwise.) However, sometimes even with the answer, I can't figure out how to get there. And occasionally, it turns out the answer key is wrong. (just for grins)

So I'm up against a toughie tonight. I can tell we're not the only ones who've died on this particular one, because when I typed in the exact problem into google, it came up as a question on yahooanswers. But there were only two response, different from each other, and neither one matches the "key."

Which is a long way of saying: Help me! Please! Can anyone tell me how to get the answer 12x + 6 to the following equation:

14x + 8 - 20x ./. 5 +2(x-1)


I am not a stupid person, but boy do these weekly math sheets make me feel like one!

TIA!

 

[BCDisneyFanatic]

You need to remember order of operations:

14x + 8 - 20x/5 + 2(x-1)...divide 20x/5 to get 4x

= 14x + 8 - 4x + 2(x-1) expand your bracket:

= 14x + 8 - 4x + 2x - 2 regroup like terms:

= 14x - 4x + 2x + 8 - 2

= 12x + 6

 

[agnes!]

This is agnes!'s daughter. This problem is all about the order of operations. Basically, you multiply/divide before you add/subtract.

14x + 8 - 20x / 5 +2(x-1)
First multiply and divide: 14x+8-4x+2x-2
Then add and subtract: 12x+6

Hope that helps!

 

[kristilew]

bless you, bless you, bless you!

You make it so easy to follow! And now I see what DD was hung up on: she has been given some phrase that has her doing the parentheses first, then trying to combine the x items, so she was ending up with negative numbers.

I obviously need to spend some time learning order of operations so that I can tutor her more efficeintly.

Thanks again, soooo much!

 

[Katie's Butterflies]

bless you, bless you, bless you!

You make it so easy to follow! And now I see what DD was hung up on: she has been given some phrase that has her doing the parentheses first, then trying to combine the x items, so she was ending up with negative numbers.

I obviously need to spend some time learning order of operations so that I can tutor her more efficeintly.

Thanks again, soooo much!

Order of operations can be really tough to remember. Here’s a handy little pneumonic I learned back in grade school for order of operations - Please Excuse My Dear Aunt Sally (parentheses, Exponents, Multiplication, Division, Addition, Subtraction). This helped me a lot in Middle and high school (and beyond!) HTH!

 

[mhsjax]

Order of operations can be really tough to remember. Here’s a handy little pneumonic I learned back in grade school for order of operations - Please Excuse My Dear Aunt Sally (parentheses, Exponents, Multiplication, Division, Addition, Subtraction). This helped me a lot in Middle and high school (and beyond!) HTH!

My daughter learned that little trick just last year, it really helps her to remember.

 

[Cindy B]

PEMDAS is your friend here.

Think of how they all work together to get your answer.

Former 5th/6th grade math teacher and I would get the kids to make their own PEMDAS acronym posters.. one was something like Please eat.. and ended with sushi, one was about panda ears, etc...

Have your daughter make up her own acronym and she will remember it-- easily.