Answer:
Your first 2 questions are correctly answered.
I think the answer to the third question is NO.
Step-by-step explanation:
You can see that the sides with 3 and 4 are adjacent, which means they cannot possibly be opposite. For a valid dice, they should be opposite because they add up to 7. Hence this net is not valid.
Answer: it will take them 4 hours to be 640 kilometers apart.
Step-by-step explanation:
Let t represent the time it will take for both trains to be 640 kilometers apart. It means that the total distance that both trains will covered in t hours is 640 kilometers.
Distance = speed × time
A train leaves Little Rock Arkansas and travels north at 75 kilometers per hour. Distance covered after t hours would be 75 × t = 75t
Another train leaves at the same time and travels south at 85 kilometers per hour. Distance covered after t hours would be 85 × t = 85t
Since the total distance covered is 640 kilometers, then
75t + 85t = 640
160t = 649
t = 640/160
t = 4 hours
Step-by-step explanation:
Note that t = d/r where t is time, d is distance, and r is rate/speed.
We can come up with two equations with the information given and the equation:
t_1 hr = (10 km)/(x km/hr)
t_2 hr = (12 km)/(x - 1 km/hr)
<em>where t_1 is the time taken to run the 10km the first day and t_2 is the time taken to run the 12km the second day.</em>
We know that 30 minutes is 1/2 of an hour and that t_1 is 30 minutes less than t_2 (as stated in the question). Therefore, we can write:
t_1 = t_2 - 1/2
Substituting the values we derived:
(10 km)/(x km/hr) = (12 km)/(x - 1 km/hr) -1/2
Then we can evaluate by multiplying by 2x(x-1) on both sides:
20(x-1) = 24x - (x)(x-1)
20x - 20 = 24x - x^2 + x
x^2 -5x -20 = 0
And we are done.
I hope this helps! :)
Answer:
D) (-1, -2)
Step-by-step explanation:
The local minimum is the bottom point on the left-side curve. Its coordinates are (-1, -2), matching choice D.
Answer:
A E and F
Step-by-step explanation:
