Answer:
Step-by-step explanation:
Distance=Speed×Time
75×4.8=360
Speed=distance÷time
360÷3=120km/h
Answer:
k=4
Step-by-step explanation:
5-7k=-4(k+1)-3
Distribute
5-7k=-4k-4-3
Combine like terms
5-7k=-4k-7
Add 7k to each side
5-7k +7k = -4k+7k-7
5 = 3k-7
Add 7 to each side
5+7 = 3k-7+7
12 = 3k
Divide by 3
12/3 = 3k/3
4=k
Let t=number of years since 1991.
Then
P(t)=147 e^(kt) ... in millions
P(0)=147 e^(0)=147
P(7)=147 e^(7k)=153
e^(7k)=(153/147)
take ln both sides
ln(e^(7k))=ln(153/147)
7k=0.0400 => k=0.005715
Year 2017=>t=2017-1991=26
P(26)=147e^(26*.005715)=170.55
Answer: in 2017, the projected population is 170.55 millions.
If we write y=f(x)=(x-h)²+k, then y-k=(x-h)². This is vertex form where the vertex is (h,k)=(3,3) so h and k are both 3. We can see this if we put x=3 in the shifted function. This is a minimum point for the function because for every other x f(x) is greater then 3. The minimum point is the vertex.