Two airplanes left an airport at the same time traveling in opposite directions. one travels at a speed of 190 miles per hour. the other travels 210 miles per hour. how long will it take for the planes to be 2000 miles apart?

190x + 210x = 2000
400x = 2000 <-- Combine like terms 

x = 5

In 5 hours they will separated by 2000 miles.

Plane 1s speed function is a = 190t and 2 is b = -210t
lets times each by 10.
1900
-2100
1900-(-2100)
4000
now 5
950
-1050
950-(-1050) 2000
the answer would be 5 hours when they are at least 2000 mi apart

38+105= 143, 39+104=143, and you will find then adding the numbers on opposite sides, moving inwards yields the answer 138 every time. because of this, you’re going to multiply 138 times the number of pairs, which is 34. therefore, 34*138= 4692(i’m sorry if it’s the wrong numbers, but it’s the right concept)