Question

8. Forrest Lumber uses the function
S(t) = -135t + 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?
7 years
5 years
8 years
9 years

Answer 1

-135t + 945 = 0
what is t now ?

Answer 2

I don't know . o:

Answer 3

add 135t to both sides and get
945 = 135t
divide both sides by 135 and get
7 = t

Answer 4

7 years

Answer 5

thanks