Answer:
Total number of notes is 11.
Step-by-step explanation:
Value is 100 rupees…
5x + 20y = 100 and x + y = 11 are the two equations.
We can simplify…
5x + 20 y - 5x - 5y = 100 - 55 = 45
15y = 45 so y = 3
x = 11 - y = 8
So, we have 8 notes of 5 rupees denomination and 3 notes of 20 rupees denomination.
I hope it helps you.
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: B) increasing for x < -4/3 and x > 4/3
decreasing for -4/3 < x < 4/3
<u>Step-by-step explanation:</u>
Graph the equation and follow the curve from left to right. If you are going up, it is increasing. If you are going down, it is decreasing.
Refer to the image below. Red is increasing. Blue is decreasing.
The vertices are at: x = -4/3 and x = 4/3
