Question 1194480
year, price
(0, 53400) and (10, 21900)
from those ordered pairs the slope is -315.
point-slope formula y-y1=m(x-x1), y slope and (x1, y1) point
y-53400=-3150(x)
or y=-3150x+53400
after 4 years, x=4 so y=-3150(4)+53400=$40,800
-
31700=-3150x+53400
so -3150x=-21700
x=6.89 years but exact is 434/63=62/9 years