Thread: Transforming Formulas

I need help with these problems and my book doesnt explain it very well.

Solve the formula I = Prt for P



Solve the formula A = P(1+rt) for r



Solve x + yr = z for z

Originally Posted by fyisvd

I need help with these problems and my book doesnt explain it very well.

Solve the formula I = Prt for P

Divide both sides by rt (as two things that are equal are still equal when
divided by the same thing)

I/(rt)=P,

P=1/(rt)

Solve the formula A = P(1+rt) for r

dicide both sides by P:

A/P=1+rt.

Subtract 1 form both sides (as two things that are equal are still equal when
the same thing is added or subracted from both)

A/P - 1 =rt

Divide both sides bt t:

(A/P - 1)/t =r,

or:

r = (A/P - 1)/t,

Solve x + yr = z for z

z= x + yr

(if something is equal to a thing, then the thing is equal to that something)

RonL