9514 1404 393
Answer:
20 minutes
Step-by-step explanation:
The trains are separating at the rate of 80 +70 = 150 km/hour. The time required to be 50 km apart is then ...
time = distance/speed = (50 km)/(150 km/h) = 1/3 h = 20 minutes
Answer : 9
Step-by-step explanation:
The answer is 9 because a constant is a number on its own, or sometimes a letter such as a, b or c to stand for a fixed number.
-x + 1/2 = x + 4 1/2
+x +x
1/2 = 2x + 4 1/2
-4 1/2 - 4 1/2
-4 = 2x
x = -2
Answer:
n = 7
n = -3
Step-by-step explanation:
4n+6 = n²-15
4n = n² - 21
n² - 4n - 21 = 0
(n-7)(n+3) = 0
n = 7
n = -3