The variable we need to isolate is P. In order to do so, we add a / 3w on both sides.
P =
Step-by-step explanation:
because we can also find out the value of x in second equation like this
3x=21
x=21/3
x=7
Answer: 
Step-by-step explanation:
We are given the following formula, used to calculate the value of an used car according to the years after the car was originally bought:

Where
is the price of the car when it was bought new, and
is the number of years the car was used.
Solving the formula with the given data:
This is the value of the car according to the formula.
However, this value can be approximated to:

Answer:
when the radicand is negative
Step-by-step explanation: