simplifying expressions I

[queenofweaves916]

Great video! I am helping my 12yr old son with his homework and this vide was so helpful. Thank you!

[h1k3r99]

I hope you can help. My problem is when finishing the simplification, I'm never sure if the number

with the variable goes first or after the number alone.

Example 1:

5 - 2 ( x + 2 [ 3 + x ] )

I got this wrong by solving as "-7-6x" when it should have been "-6x-7"

Example 2:

4 - 9 ( 2 x - 3 ) + 7 ( x - 1 )

I got this wrong by solving as "-11x+24" when it should have been "24-11x"

I assume I'm missing some rule, but I'm not sure what it is :(

Thanks in advance.

[robichaudd]

@h1k3r99 Both ways of showing the answers are valid. When in doubt, the safest way to show an answer is with descending powers of the variable. So for -7-6x, show -6x-7. Not sure why your -11x+24 answer would be marked wrong. There might have been some detail in the problem that suggested leaving the answer in a certain format.

[xXD3ADFR0NTI3RXx]

I have to simplify the expresion an write the property D:

[taytay8900]

Thanks SO much! My math teacher gave us this worksheet for pre-algebra and I kept asking for help but she ignored me. I spent forever looking at tutorial videos but none of them helped. Now I actually get it. :)

[cshcrazy]

How do i Divide by 0???HELP! My calculator sucks and says ERROR now i don't work ):

[j2cool2]

I hope you still see this since the upload is a few years old. Could you help with: simplify (8x)(2y)(3z) the next problem is the same only they all have to be added. How can this be done if there are no like kinds? Thank you

[JRowns475]

Wasnt sure if would ever get this down.

[randomfat32]

uhhhh i dont get it

[jaqdudley]

Omg thank u so much!

[11yo1yo]

this was gr8 it really helped me in my exam! :)

[biggee316]

5+3(x-2) shouldn't it be 5x-10+3x-6 then 8x-16? cus i thought you had to distribute the 5 into x-2 and the 3 into x-2? wasn't that what was supposed to happen?

[robichaudd]

@biggee316 In 5+3(x-2) the 5 is being added to 3(x-2), so first we multiply the 3 with (x-2), then add 5 to the result. If the expression was instead (5+3)(x-2), then both the 5 and 3 would multiply the (x-2) in the way you described in your comment.

[1234LMAO12345]

i gottcha :D

[emerica4life12]

thank you

[x3simplychay]

thank you!

[Totallyawesomelegos]

THANK YOU SOOOOOOOOOO MUCH I am only in 6th grade and my algebra teacher is so mean and I had a quiz tomorrow and now I understand thank you!!!!!!

[roshpiansay]

nice writing

[SasanSB12]

3x -(2y - (2x - 2y))...I'm lost trying to figure this out =( I need to pass an entrance exam next month, and need to catch up on most of my algrebra...please reply asap! >_<

[Y2JxFan]

4x + 3(4 - x)

4x + 12 - 3x

= 1x+ 12 or 12 + 1x??

[robichaudd]

@Y2JxFan Both are correct, kind of like 6+3 is the same as 3+6.

[tokenaznguy21]

@robichaudd yea but i heard from some teachers that they want the variables first and if they were raised to the 2nd power then the highest exponet would go first then so on. any ideas

[robichaudd]

@tokenaznguy21 Yes, the more acceptable way to write it is x+12. But 12+x is technically correct too.

[rfox012]

@Y2JxFan THANK YOU VERY MUCH YOUR THE BEST KK :)

[AnnessainFlorida]

I am a middle school reading teacher who found your algebra demo videos on line while helping a friend who is currently in college (there is a reason why I DON'T teach math - LOL). Your teaching methods are outstanding! I wish I'd had an instructor who taught algebra the way you do back when I was in high school or even college. My hat is off to you!

[LadiJrock]

this reALLY HELPS YOURE GREAT

[PrettySkitty16]

please help with these

4x+3(x+6)

5x+2(2x+3)

[230halfangel230]

4x+3x-12

7x-12

5x+4x+6

9x+6

[robichaudd]

@230halfangel230 Second one looks good, first one ends with +18 instead of -12. Thanks for taking the time to reply to that question 230halfangel230 :-)

[blackeagle1173]

could you show me where i can find help for free to help me with my illinois h school entrance exam??? id appreciate it.

[robichaudd]

not sure where, sorry

[blackeagle1173]

its okay thanks =(

[Mattdude411]

Thank you so much this helped so much more than my stupid subsitute teacher :)

[jadea98]

what Grade work is this????

[russwest413]

8th or 9th grade

[M4A1machine]

@russwest413 grade 7

[blackeagle1173]

@jadea98 this is algebra 1

[funnybutscary75]

THANKS

[Animangarocks]

wow ty so much, i think my algerbra teacher sucks kinda, she goes way to fast through the problems, i was trying to copy the problem down and shes already finishing up the problem and starting on a new one, its so annoying xD so yha this helps alot

[ryubakura27722]

is there a book that have all the shortcuts and secrets of algebra ??

[robichaudd]

Some teachers I used to work with liked tutoring students with the book Forgotten Algebra, but I never used it so can't say for sure.

[ryubakura27722]

so the title is "Forgotten Algebra" ? I try to search for it

[robichaudd]

Yeah, it's at amazon, search "Forgotten Algebra: A Self-Teaching Refresher Course". Like I said, I haven't used it before so can't say how good it is, but I new some teachers who used it alot.

[TwiNerd27]

hi i have A LOT of problems with simplifying expressions, & i was wondering if you could send 10 problems to me, with the answers...i need to practice this BADLY!

thanx

[robichaudd]

Yeah, lots of students want practice with this. Try googling "simplify expressions practice problems", you'll find plenty of websites with problems and answers.

[aballernamedsila]

thnx... i needed dat

[ShayShaysroom]

Thank you for helping me!!!

[budgiebreder]

thx i've always used the "shortcut method" i was never tought differently. personally i'd just end up confused doing it the other way. (problem 2)

[UJustR4pedMe]

do you have a vid using 2 variables

[robichaudd]

not for simplifying, just for factoring

[ChelseaPutmanCarey]

I thought the last step was to divide the variable and the last number you got?...

thanks so much for the help.. i was struggling in class today. between me and you, i boo hooed a little... i didn't pay much attention much in 9th grade. im in 10th geometry.. its hard to keep up with the Simplifying Expressions with angles and such....

But..Thank you so much... it, really did help me... =]

[robichaudd]

You only do that last step when solving equations. Like 3x=6, the last step is to divide by 3 both sides. With expressions, like 3x+6, you just leave it. You can't introduce something new, like divide by a number or add by a number, unless you're doing it to both sides of an equation - that way the equation stays balanced.

[dreamerchaser101]

thanks.

random question but what type of pen is that?

[robichaudd]

it's a papermate felt tip marker. expo wet erase fine tips also work well.

[balz174]

very helpful. you explain this very well thanks