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
Answer:
x > -5
Step-by-step explanation:
Answer:
Step-by-step explanation:
-5x - 10y = -30
5x + 3y = 2
-7y = -28
y = 4
x + 8 = 6
x = -2
(-2, 4)
Answer:
1.345*10^7
Step-by-step explanation:
Here we need to rewrite 13,450,000 in scientific notation, which looks like x.xx*10^n.
To move the decimal point in 13,450,000 to its proper place between the 3 and the 4, a move of 7 digits, we need to multiply 1.345 by 10^7.
13,450,000 in scientific notation is 1.345*10^7.
The answer would be 5,875.00
