Question

WILL MEDAL & FAN. Solve for r, I have the answer but im confused on how it was gotten
P= A/1+rt
do I multiply by the denominator?
Answer is: r= A-P/pt
Posting this again cause I cant get anyone to help and this bump thing doesn’t seem to be working…

Answer 1

\[P= \frac{ A }{ 1+rt}\]

Answer 2

Actually, you can multiply by the denominator, but since it is 1, it can be ignored as any number divided by 1 equals itself by the Identity Property of Division.

Also your answer of r=A-P/pt isn't exactly correct, but I think you made a typo and meant
\[r = \frac{ A - p }{ t }\]
since you seemed to have everything mixed up.

Answer 3

ok so you multiplied by the t only?

Answer 4

No, I subtracted both sides by A and divided both sides by t to solve for r.

Answer 5

Sorry, Im a little slow with the all variable equations >.<
Ok so the 1 is basically ignored because of the property so by subtracting the A you break it from being a fraction?

Answer 6

Oh wait, I realized your typo in the problem that equals P. Hold on a second.

Answer 7

Says in the answer key \[\frac{ A-P }{ Pt }\]

Answer 8

2 uppercase P?? o__o

Answer 9

Honestly, I also don't see how they found that.

Answer 10

I did this:
\[P = \frac{ A }{ 1 + rt }\]
This is how to solve for R.

Rewrite P and p/1 and use a proportion to get
\[P(1 + rt) = A\]

Then divide both sides by P to get
\[1 + rt = \frac{ A }{ P }\]

Subtract 1 from both sides then divide both sides by t.
\[r = \frac{ \frac{ A }{ P } - 1 }{ t }\]

Yes, it is strange but this is how I did it with my methods.

Answer 11

yes it makes sense. so im guessing insead of the -1 they substitute it by another P

Answer 12

Wait, I used a website and found this method:

Answer 13

There is another answer choice of \[r=\frac{ P-A }{ 1+t }\]

Answer 14

but it still says the right one is the one i said

Answer 15

My mistake since I don't really always see other methods. But now I see the pathway you chose after seeing this on the website.
\[P = \frac{ A }{ (1 + rt) }\]
\[P = \frac{ A }{ rt + 1 }\]
\[(rt + 1)P = A\]
\[r = \frac{ a - P }{ Pt }\]
Yes you are correct. Sorry I didn't see how you arranged the variables in that manner earlier.

Answer 16

Ok so you divided by the P in the (rt+1)P=A

Answer 17

But how is it that the r is left alone when its stuck to the t and +1

Answer 18

@MathematicsNerd

Answer 19

\[rtP + P = A\] Apply distributive property
\[rtP = A - P\] Subtraction Property pf Equality
\[r = \frac{ A - P }{ Pt }\] Divide both sides by Pt or tP