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:
Tax is $6.64
Step-by-step explanation:
From what we know dinner is $83 and the tax is %7.5
Step 1) Round the %7.5 to %8
Step 2) Turn the %8 into -> 0.08
Step 3) Multiply 0.08 by 83 which is 6.64
Step 4) Add 6.64 with 83
Answer) Together the full price of the meal is $89.64
Hope this helped! :)
Answer:
x = -8
y = 9
Step-by-step explanation:
to solve this expression using simultaneous equation, we would say let
y =9............................................. equation 1
6x + 5y =-3............................................equation 2
substitute equation 1 into equation 2
-3 = 6x + 5y............................................equation 2
6x + 5(9) = -3
6x + 45 = -3
collect the like terms
6x = -3-45
6x = -48
divide both sides by the coefficient of x which is 6
6x/6 = -48/6
x = -8
therefore y = 9
x = -8
Answer:
Plot a point at (0,-3) and (2,-2) then connect.
Step-by-step explanation:
Use y=mx +b to guide where you graph the line. b is the y -intercept and shoud be graphed on the y-axis. m represents the slope which is rise/run. To graph the line, mark -3 on the y-intercept. Then plot the next point 1 unit up and 2 units over at (2, -2).