Answer:
1994
Step-by-step explanation:
Answer:
- train: 40 kph
- plane: 140 kph
Step-by-step explanation:
Let t represent the speed of the train in km/h. Then 4t-20 is the speed of the plane. Travel times are the same, so we can use the formula ...
time = distance/speed
and equate the travel times.
110/t = 385/(4t-20)
Cross multiplying gives ...
110(4t -20) = 385t
440t -2200 = 385t . . . . . eliminate parentheses
55t -2200 = 0 . . . . . . . . . subtract 385t
t -40 = 0 . . . . . . . . . divide by 55
t = 40 . . . . . . . . . . . add 40; train's speed is 40 kph
4t -20 = 140 . . . . . . find plane's speed; 140 kph
The train's speed is 40 km/h; the plane's speed is 140 km/h.
_____
<em>Check</em>
Train's travel time = 110 km/(40 km/h) = 2.75 h.
Plane's travel time = 385 km/(140 km/h) = 2.75 h.
9514 1404 393
Answer:
y = -3x^2 +3x +6
Step-by-step explanation:
For roots p and q, the equation can be written as ...
y = a(x -p)(x -q)
The value of 'a' must be determined so that the product <em>apq</em> is equal to the y-intercept. One could say that the formula is ...
y = (y-intercept)/(pq)·(x -p)(x -q)
For your given values of p = 2, q = -1, y-intercept = 6, this becomes ...
y = 6/(2(-1))(x -2)(x +1)
y = -3(x^2 -x -2) . . . . . simplifying a bit
y = -3x^2 +3x +6
Answer:
The answer is D. 393ft
Step-by-step explanation:
So if you do 62.5•2=125
Then you do 125•3.14=392.5
After that then you round 392.5 and you get 393
theres your answer.
