Math Is Fun Forum

survival

Member

Registered: 2011-04-03

Posts: 655

Algebra problem--solution set

Solve and check the following equation. What is the solution set?

-(7 - 6a) - (20 + 5a) - 1 = - (7 - 5a) + ( - a ) + 6
 
Thank you~

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Algebra problem--solution set

Hi;

Where have you been?

a = - 9

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

survival

Member

Registered: 2011-04-03

Posts: 655

Re: Algebra problem--solution set

Thank you. I have been working on a math project. Now, I am going to try and finish my homework. It's nice to be back.
Another long equation:

-7m + 64 - 8 (m - 6) = 9m - (6m - 5) - 4m + 9

Last edited by survival (2011-04-22 14:18:00)

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Algebra problem--solution set

Hi;

m =7

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

survival

Member

Registered: 2011-04-03

Posts: 655

Re: Algebra problem--solution set

Thanks much! I have one of a word problems that i have worked too death, without success, if i can find it in all my papers.

-[5z - (11z + 1)] = 1 + (5z +2)

Do you do this in your head or have to write it down?

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Algebra problem--solution set

Hi;

z = 2

Yes, these can be done in your head.

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

survival

Member

Registered: 2011-04-03

Posts: 655

Re: Algebra problem--solution set

It is a gift to know this Math I think. Do you know Geometry? I have that in another week, it should be interesting.
- 8p - 5 (5 - 3p) = 2 (p - 4) - 47

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Algebra problem--solution set

Geometry is okay. I prefer numerical analysis, combinatorics and probability.

It is not a gift. I just have been doing it longer than you.

p = -6

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

survival

Member

Registered: 2011-04-03

Posts: 655

Re: Algebra problem--solution set

Thank you.
Last semester/this is the first math I've had since high school. I think it's called a math phobia.

Here is a word one: Looks like dabbling in chemistry.

A chemist has two solutions of H2SO4 (The 2 and 4 are tiny, not to the power but opposite.) One has a 40 % concentration and the other has a 25% concentration. How many liters of each solution must be mixed to obtain 50 liters of a 34% solution?

____ liters of the 40% solution and ____liters of the 25% solution must be mixed to obtain 34% solution of H2S04.
Round to nearest tenth. (anywhere that I list the H2S04, the 2 and 4 are tiny below.

Last edited by survival (2011-04-22 18:15:38)

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Algebra problem--solution set

Hi survival;

That substance is Sulfuric acid. It is wriiten like this:

I am getting for the first one mix 30 liters of the 40% an 20 liters of the 25%. Please check it.

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

survival

Member

Registered: 2011-04-03

Posts: 655

Re: Algebra problem--solution set

Ok, i will check and edit this post to tell you.

You are exactly correct! THANK YOU! I remember this acid from Geology and Biology. Sometimes, we used it to determine different identities of rocks in the lab.
A good chemist you are, as well as mathematician. The sciences go together.

I solved a couple earlier that mixed ml. of lots of liquids, but I got frustrated and just guessed them accurately.

Here is another:
The body mass index, I, can be used to determine an individual's risk for heart disease. An index less than 25 indicates a low risk. The body mass index is given by the formula, or model, I = 700W/H^2, where W = weight in pounds, and H = height in inches. Jerome is 76 inches tall. What weights will keep his body mass index between 24 and 33?

Jerome's body mass index will fall between 24 and 33 for the set of all weights such that ____ < W < ____.
Round to nearest whole number as needed.

Last edited by survival (2011-04-22 20:11:02)

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Algebra problem--solution set

I am getting 198 and 272 in pounds.

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

survival

Member

Registered: 2011-04-03

Posts: 655

Re: Algebra problem--solution set

It is correct!
I hope you are not getting tired. This is a lot of thinking.

The linear model below gives the approximate enrollment in thousands, for degree-granting institutions in a certain city, from the year 2003, where x = 0 corresponds to 2003, x =1 to 2004 and so on.
y = 0.2157x + 15.53

a. What is the projected enrollment for Fall 2012?
b. In what year is the enrollment projected to reach 18 thousand?
a. The projected enrollment for Fall 2012 is ____thousand
Round to nearest tenth.
There is a b. part, but cannot get it till this is typed in.
Thank you!

Last edited by survival (2011-04-22 21:12:50)

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Algebra problem--solution set

For a) I get 17.4713 in thousands, so round it to 17.5

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

survival

Member

Registered: 2011-04-03

Posts: 655

Re: Algebra problem--solution set

Hello again:
It was correct.
Here's the B part.
The enrollment is projected to reach 18 thousand during the year____.
It is nearly morning here, so I guess I need to call it a night or day.
thanks for helping me and I will check in later today or night.
Goodnight.

Last edited by survival (2011-04-22 21:16:02)

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Algebra problem--solution set

2015 is when it will reach slightly more than 18000.

Goodnight and see you tomorrow.

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.