Prism99

You need to solve for a. The = is like a teeter-totter; if you add something to one side, and add the same amount to the other side, it stays =.

To get a on the left side, add a to both sides.
5+a = 51-a+a
5+a = 51 (because -a+a on the right is zero)

To get a alone on the left, subtract 5 from both sides.
5+a-5 = 51-5
a = 51-5 (because 5-5 on the left is zero)
a = 46

Once you are used to this, you can do it all in your head. I would have immediately re-written the equation as:
a=51-5
a=46

Lneal

Prism99 wrote To get a alone on the left, subtract 5 from both sides.
5+a-5 = 51-5
a = 51-5 (because 5-5 on the left is zero)
a = 46

Once you are used to this, you can do it all in your head. I would have immediately re-written the equation as:
a=51-5
a=46[/quote]



Okay are you saying that it's correct to re-write the problem?

17 = 22 - u


u = 22 - 17 = 5

Because that is much easier to understand than "jumping the shark" ( which my instructor said originated from the show Happy Daz.) I know you are wondering how that has anything to do with math.

Prism99

Yes!!!

Lneal

It's that easy? Why do they make it sooooooooo hard to learn? Thank you so much
:thumbup: :thumbup: :lol: :thumbup:

Lisanne

It did originate with Happy Days, when Fonzie jumped over a shark on water skis. I don't know how it got to be a math term, though.

Lneal

My ABLE instructor said it has something to do with the number on one side of the equation jumping to the opposite side of the equation and changing its sign to the opposite. Like if it was a positive it will become a negative. (Sounds drastic or like jumping ship) She used it in this math example. I may be able to explain it better when I return to class next week and get some more details.

I found this math web site which is free, if anyone here would want to check it out. It will allow you to view parts of the lessons. But if you sign up, at no cost, you may view the complete lessons. http://www.brightstorm.com/

Lisanne

That's what I'd guessed, about the meaning.

You just have to be careful about what you move to the other side of the equal sign. For example,

x - (1 - 5) = 3

This would be wrong: x = 3 + 1 + 5 = 9
That first minus sign applies to the entire quantity inside the parentheses. It's actually a -1 and needs to be multiplied with each term in the parentheses.
So it's x -1 + 5 = 3
and then x = 3 + 1 - 5 = -1

MadQuilter

Lisanne,

I think if you break it into the individual steps of how you get there, it might be easier to understand.

x - (1-5) = 3 (solve the parens)
x - (-4) = 3 (multiply a negative 1 times a negative # = positive #)
x + 4 = 3 (subtract 4 from both sides)
x = 3 - 4 = -1

Lneal

I really need some help with a problem that ask me to Simplify.
You ladies have been so assisting when I ask and I am really starting to see an improvement in my algebra skills. However, just when I think I'm gaining ground, a new step comes up.
I understand to simplify means to get it into the simplest form, which is also solving, right? This is my problem today.

5y + 13 = 2y - 2

The correct answer, marked on my test, is -5. I am trying to redo my wrong answers to learn how to do the steps right. I just don't know how to do it.

Here is another one I missed.

-2(x - 5) + 4 = 4(2x-4) The correct answer is 3, but I don't understand how to do it. Thanks in advance!!

barnbum

5y + 13 = 2y - 2
Remember--get all the y's on one side--all the whole numbers on the other.
So, move the 2y to the other side, or subtract it from both sides so everything is even. Once it's taken away from both sides you get 3y+13=-2.
now get the whole numbers on one side by subtracting 13 from both sides. So then you have 3y=-15. Ask yourself what multiplied by 3 will give me -15 and it's -5.

The correct answer, marked on my test, is -5. I am trying to redo my wrong answers to learn how to do the steps right. I just don't know how to do it.

Here is another one I missed.

-2(x - 5) + 4 = 4(2x-4) The correct answer is 3, but I don't understand how to do it. Thanks in advance!![/quote]
-2(x-5) + 4 = 4(2x-4)
Here you go!
-2 times x=-2x, then do
-2 times -5=10
4 times 2x = 8x, then do
4 times 4 = 16

So, once you multiply all that out you get:
-2x + 10 + 4 = 8x-16
Remember you need to get the x alone, so, next add 2x to each side to cancel out the -2x
and you have 10 + 4 = 10x-16
Then, get the 16 out of there by adding 16 to each side--which cancels out the 16 on the right--and you get:
14+16=10x
Then 30=10x and what multiplied by 10 = 30? 3, so x=3.