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Mathishard

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Rearrange formulae. Step by Step help?

Hi, I am looking for any help regarding rearranging formulae including step by steps on how you get to the answers.
I have answered all the questions but feel they may be wrong.

1) F-   C=5(F-32) / 9

2 h-  t=1/4 Sqrt(5a/h)

3) t-  V=1/3πt^2h                  (π =pi)

4) t-  Pa = w(v-t) / g

5) y=2x+3 / 5x-2

I am working at A-Level.

My answers are as follows; (If could reply with workings and how you get to your answer that would be much appreciated)

1) F = C9/5 + 32
2) h = 5a/4t^2    (Could also be h=5a/(t/1/4)^2)
3) t = Sqrt (V / 1/3πh)
4) t = (Pag/ W) -v
5) x = 2y+3/5y-2

It is hard to show superscripts and square roots/ fractions in plain text so if you do not understand some of the questions or answers I have written please ask and I will send an image to you.

I am most concerned about question 3 being totally wrong?

Thanks to all of you for putting your own time into helping my studies!

PS: If anyone knows a website / software / app that provides step by step solving algebra questions such as rearranging formulae that would be awesome!

Thanks in advance.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Rearrange formulae. Step by Step help?

Hi;

I will provide one possible solver with this warning:

Algebra is the backbone of math. Learning its manipulations and tricks is mandatory. If you become too dependent on software in the early stages of your training you will have problems later on. It is best to learn how to do it by hand first and only then when you are a hardnosed imbecile like me should you learn of the existence of these things.

https://www.symbolab.com/solver/solve-f … calculator

In the early eighties when the first microcomputers came out, I saw that as an opportunity to do probability problems without knowing much math. This naive opinion led me to buy a TRS-80 model 3. I quickly learned Basic and Assembly language and began to do probability problems using them. I got lots of answers and soon was dominating my profession using those answers. But there were other problems...Problems I could not solve because they took too long. Pretty soon, I was asking how to speed my simulations up. This led right back to Probability, Calculus, Combinatorics, Numerical Analysis and of course more Algebra. So I learned this important lesson, to effectively use a computer one has to know lots of math.

May I see how you did the first one, step by step?

1) F-   C=5(F-32) / 9

---

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.

mathishard

Member

Registered: 2016-11-14

Posts: 4

Re: Rearrange formulae. Step by Step help?

Hi;

I will provide one possible solver with this warning:

Algebra is the backbone of math. Learning its manipulations and tricks is mandatory. If you become too dependent on software in the early stages of your training you will have problems later on. It is best to learn how to do it by hand first and only then when you are a hardnosed imbecile like me should you learn of the existence of these things.

https://www.symbolab.com/solver/solve-f … calculator

In the early eighties when the first microcomputers came out, I saw that as an opportunity to do probability problems without knowing much math. This naive opinion led me to buy a TRS-80 model 3. I quickly learned Basic and Assembly language and began to do probability problems using them. I got lots of answers and soon was dominating my profession using those answers. But there were other problems...Problems I could not solve because they took too long. Pretty soon, I was asking how to speed my simulations up. This led right back to Probability, Calculus, Combinatorics, Numerical Analysis and of course more Algebra. So I learned this important lesson, to effectively use a computer one has to know lots of math.

May I see how you did the first one, step by step?

1) F-   C=5(F-32) / 9

The provided link cannot give me an answer for question 3? Unsure why.

My step by step for question 1 is:
C=5(F-32) / 9

x9 (To get rid of the /9)

C9 = 5(F-32)

/5 (To get rid of the multiplication)

C9/5 = F-32

+32 (To get rid of the -32)

(C9/5) + 32 = F

Flip it around, F= (C9/5) +32

Thanks.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Rearrange formulae. Step by Step help?

That is fine except we write 9C instead of C9. So where are you having a problem?

The provided link cannot give me an answer for question 3? Unsure why.

Your Sqrt (V / 1/3πh)  what is in the denominator?

---

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.

mathishard

Member

Registered: 2016-11-14

Posts: 4

Re: Rearrange formulae. Step by Step help?

the whole part of 1/3PIh is the denominator.

The 1/3 is a fraction in itself.

After going through the questions again, I have different answers for some.

I am confused for question 2.

If I refine the right side of the equation instead of moving the 1/4 over to the left I divide the whole right side by 4. Since times by 1/4 is the same as dividing by 4.
That makes it t= (Sqrt 5a/h) / 4
Square both sides- t^2 = 5a/16h
Times by 16h = 16t^2h = 5a
Divide by 16 = t^2h = 5a/16
Divide by t^2 = h = 5a/16t^2
...
So I get h= 5a / 16t^2 for my answer instead of h= 5a/4t^2 from earlier when I move the 1/4 over to the left.

Also, I now get
QUESTION 3) T = Sqrt 3V / PIh

Since I times V by 3 instead of keeping 1/3 as a fraction.

I hope that makes sense.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Rearrange formulae. Step by Step help?

Does question 2 look like this:

---

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.

mathishard

Member

Registered: 2016-11-14

Posts: 4

Re: Rearrange formulae. Step by Step help?

it's not h- t its just t = and the rest is fine. Yes.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Rearrange formulae. Step by Step help?

Hi;

So I get h= 5a / 16t^2 for my answer instead of

I am getting

---

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.

mathishard

Member

Registered: 2016-11-14

Posts: 4

Re: Rearrange formulae. Step by Step help?

Hi;

So I get h= 5a / 16t^2 for my answer instead of

I am getting

Can you post your step by step and explain please since I have to it too just want to confirm.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Rearrange formulae. Step by Step help?

Hi;

---

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.