Newton's Law of Cooling
Tf=Ts+(Ti-Ts)e^(-kt) where Tf is temp at time t, Ts is temp of surroundings, Ti is temp of object/fluid. So we need to find k first.
200=68+(210-68)e^(-10k)
132=142e^(-10k)
132/142=e^(-10k)
ln(132/142)=-10k
k=-ln(132/142)/10
k≈0.0073 so
T(t)=68+142e^(-0.0073t) so how long until it reaches 180°?
180=68+142e^(-0.0073t)
112=142e^(-0.0073t)
112/142=e^(-0.0073t)
ln(112/142)=-0.0073t
t= -ln(112/142)/(0.0073)
t≈32.51 minutes
(2,-5),(-1,4)
slope = (4 - (-5) / (-1 - 2) = (4 + 5) / -3 = -9/3 = -3 <==
7/9 is 77.7, as far as I know.
Answer:
Step-by-step explanation:
f(x) = -x + 71 - 4 is a straight line. It does not have a vertex.
