42 because--------------------------------------------------------------................................
-9 + 6 + (-7) +3=
-9 +6 = -3
-3 + (-7)= -10
-10 +3= -7
9514 1404 393
Answer:
5 seconds
Step-by-step explanation:
Suppose the front parts of the trains meet at point A. Since both are the same length and traveling the same speed, each will pass point A in time ...
time = distance/speed
time = (1/18 mi)/(40 mi/h) = (1/720 h) × (3600 s)/(1 h) = 5 s
That is, the rear part of each train will be at point A 5 seconds after the front part.
The rear parts will pass each other 5 seconds after the front parts meet.
Since 7 is greater than 5, you input it into the last equation.
2•(7) -7
14-7
7
The answer is 7!
There may be an error with the first answer choice because it can't have a negative. The problem is x + 2.6 = 3.5 correct?
Hope this helps!
