Answer:
Distance between Montpelier and Columbia is 1020
Step-by-step explanation:
51 mi/hr average:
d = 51 t
60 mi/hr average:
d t = 60*(t-3)
Substitute (1) into (2)
51 t = 60*(t-3)
51 t = 60 t + 180
9 t = 180
t = 20
d = 51 t
= 51 (20)
= 1020
let see distance is 1020 lets check
51 t = 60 * (t-3)
51 (20)= 60* (20-3)
1020 = 60*17
1020 = 1020
Answer:
x= -11/4 is a maximum.
Step-by-step explanation:
Remember that a function has its critical points where the derivative equal zero. Therefore we need to compute the derivative of this function and find the points where the derivative is zero. Using the chain rule and the product rule we get that

And then we get that if
then
. So it has a critical point at
.
Now, if the second derivative evaluated at that point is less than 0 then the point is a maximum and if is greater than zero the point is a minimum.
Since
x= -11/4 is a maximum.
Multiplication comes before any subtraction...so do 10 x 5 first