Answer: 52.94
Step-by-step explanation:
Length of train A = 480m
Tunnel length = 1320m
Time taken to cross tunnel = 2 mins = 120sec
Length of train B = 420m
Train B is slower than train A
Difference between their speed = 18km/hr
18km/hr = (18×1000)/3600 = 5m/s
Speed of train A :
Speed = distance / time
Speed = 1320 / 120 = 11m/s
Therefore, speed of train B :
(11 - 5)m/s = 6m/s
Relative speed of the two trains is therefore;
(Speed of A + speed of B)
Note : they are moving in opposite direction
( 11 + 6)m/s = 17m/s
Therefore time taken to cross each other :
(Sum of the length of both trains / relative speed of the trains)
Time taken = (480m + 420m) / (17m/s)
Time taken = 900m / 17m/s
Time taken = 52.94s
The second option is the answer
Collect like terms and you'll get -2 - 3(a - b)
Answer: the y-coordinate that completes the point is 5.
Explanation:
An ordered pair (x, y) indicates the x-and-y coordinates of a general point, where x is the input value of a function and y is the output value.
The output value is y = f(x) and must be found applying the rule (function) to the given input value.
In this case the rulte is f(x) = - 3x + 2, and the input value, x, is - 1 (the first value of the ordered pair).
This is the mathematical procedure:
- x = - 1
- f(x) = f (-1) = -3 (-1) + 2 = 3 + 2 = 5.
