Question

S(t) = -105t + 945 to determine the salvage value, S(t), in dollars, of a table saw t years after its purchase. How long will it take the saw to depreciate completely? A. 11 years B. 8 years C. 7 years D. 9 years

Answer 1

Answer:

D

Step-by-step explanation:

When something depreciates completely, it will have a total value of 0 dollars. Therefore, set the equation to zero and solve for t to find the years.

$S(t)=-105t+945\\0=-105t+945\\-105t=-945\\t=9$

Therefore, the table saw will completely depreciate after 9 years.

Answer 2

Answer:

$\large \boxed{\sf \bold{D.} \ 9 \ years}$

Step-by-step explanation:

$S(t) = -105t + 945$

For the value to depreciate completely, the amount has to be equal to 0 dollars.

Set S(t) to 0.

$0 = -105t + 945$

Solve for the time t.

Subtract 945 from both sides.

$0 -945= -105t + 945-945$

$-945=-105t$

Divide both sides by -105.

$\displaystyle \frac{-945}{-105}=\frac{-105t}{-105}$

$9=t$

It will take 9 years for the saw to depreciate completely.