I am trying to figure this problem out.
Two planes start from the same airport and fly in opposite directions. The second plane starts 1/2 hour after the first plane, but its speed is 33 miles per hour faster. Find the airspeed of each plane if, 2 hours after the first plane departs, the planes are 3000 miles apart.
STEP 1:
Let x be the speed of the plane that leaves first and let y be the speed of the plane that leaves second. Complete the following system of equations which describes this situation.
33 = y - x
3000 = 2x + 3 (y/2)
STEP 2:
Find the solution to the system of equations in Step 1. Enter your answer in the form (x, y).
STEP 3:
Rewrite your result from Step 2 in the context of the problem.
The first plane that leaves the airport travels at 843 mph.
The second plane that leaves the airport travels at _____ mph.
Can anyone help me figure out the mph for the second plane. 10 points to the best answer!! Thank you so much.
Two planes start from the same airport and fly in opposite directions. The second plane starts 1/2 hour after the first plane, but its speed is 33 miles per hour faster. Find the airspeed of each plane if, 2 hours after the first plane departs, the planes are 3000 miles apart.
STEP 1:
Let x be the speed of the plane that leaves first and let y be the speed of the plane that leaves second. Complete the following system of equations which describes this situation.
33 = y - x
3000 = 2x + 3 (y/2)
STEP 2:
Find the solution to the system of equations in Step 1. Enter your answer in the form (x, y).
STEP 3:
Rewrite your result from Step 2 in the context of the problem.
The first plane that leaves the airport travels at 843 mph.
The second plane that leaves the airport travels at _____ mph.
Can anyone help me figure out the mph for the second plane. 10 points to the best answer!! Thank you so much.
-
-x + y = 33
2x + (3/2)y = 3000
multiply first equation by 2 and add to the second equation
-2x + 2y = 66
2x + (3/2)y = 3000
---------------------------
(7/2)y = 3066
y = 3066(2/7) = 876 miles per hour
-x + 876 = 33
x = 843 miles per hour
(x, y) = (876, 843)
2x + (3/2)y = 3000
multiply first equation by 2 and add to the second equation
-2x + 2y = 66
2x + (3/2)y = 3000
---------------------------
(7/2)y = 3066
y = 3066(2/7) = 876 miles per hour
-x + 876 = 33
x = 843 miles per hour
(x, y) = (876, 843)
-
Let speed of plane A = x mph
After 1/2 h travels x/2 miles
Speed of plane B = x + 33 mph
After 2h plane A has travelled 2x miles
After 2 hours plane B has travelled (3/2)(x + 33) miles
2x + (3/2)(x + 33) = 300
4x + 3x + 99 = 6000
7x = 5901
x = 843
Speed of first plane = 843 mph
Speed of second plane = 876 mph
After 1/2 h travels x/2 miles
Speed of plane B = x + 33 mph
After 2h plane A has travelled 2x miles
After 2 hours plane B has travelled (3/2)(x + 33) miles
2x + (3/2)(x + 33) = 300
4x + 3x + 99 = 6000
7x = 5901
x = 843
Speed of first plane = 843 mph
Speed of second plane = 876 mph
-
y=x+33
=843+33
=876 mph
=843+33
=876 mph