Anew car worth $20,000 loses 20% of its value every year. is the value of the car represented by a linear or exponential function?

exponential functiony=$20,000(0.8)^xwhere  x  = time

exponential function: y=a(b)x

a  = principal valueb  = rate (growth or decay)x  = time

since the initial value (principal amount) is $20,000 it needs to represent the  a  value. the rate would be a decay since it is losing 20% of its value every year (1−0.2=0.8). the time is in year. so it is:   y=$20,000(0.8)^x

hi,

i'm 75% sure the answer is 1,1 to both lines.

have a great day