Two planes which are 1680 miles apart fly toward each other. their speeds differ by 40 mph. if they pass each other in 2 hours what is the speed of each?

Speed of slower plane = 400 mph

Speed of the faster plane = 440 mph

Step-by-step explanation:

Let x be the speed of the slower plane, in mph.

Thus;  the speed of the other plane is x +40 mph.

The distance between two planes decreases at the rate;

x + (x+40) = 2x + 40 mph.

We get the equation

1680/(2X + 40) = 2.

Solve the equation;  

We multiply both sides by (2x + 40), to get

1680 = 2*(2x + 40),  

1680 = 4x + 80,

4x = 1600.

Hence,

x = 1600/4  

  = 400 mph.

Therefore; the speed of the slower airplane is 400 mph, while

The speed of the faster is 400 + 40 = 440 mph.

correct answer is infinitely many solutions

step-by-step explanation:

2(2x + 3) = -4 + 2(2x + 5)

solving the above equation:

4x + 6 = -4 +4x +10

combining like terms

4x -4x = -4+10-6

0=0

since both sides are 0=0, we end up into true statement it means it has infinite many solutions.

so correct answer is infinitely many solutions

i can answer this if i have the answer choices