8.5 = 17/2 and 26/e^(0.8 x) = 26 e^(-4 x/5):
17/2 = 26/e^((4 x)/5)
17/2 = 26/e^((4 x)/5) is equivalent to 26/e^((4 x)/5) = 17/2:
26/e^((4 x)/5) = 17/2
Divide both sides by 26:
e^(-(4 x)/5) = 17/52
Take reciporicals of both sides:
e^((4 x)/5) = 52/17
Take the natural logarithm of both sides:
(4 x)/5 = log(52/17)
Multiply both sides by 5/4:
Answer: | x = 5/4 log(52/17)=1.3975........etc.
