Question 845178
AN AIRPLANE AT 19,200 FEET IS DESCENDING AT A RATE OF 40 FEET PER SECOND ANOTHER AIRPLANE TAKES OFF AND ASCENDS AT A RATE OF 60 FEET PER SECOND AFTER
 HOW MANY SECONDS WILL THE AIRPLANES BE AT THE Same height what is the height
:
Write an equation for each plane,
let t = flying time in seconds for each plane
Descending: h = 19200 - 40t
Ascending: h = 60t
:
h = h, therefore
60t = 19200-40t
60t + 40t = 19200
100t = 19200
t = 19200/100
t = 192 seconds
:
Find the height: 
h = 19200 - 192(40)
h = 19200 - 7680
h = 11,520 ft 
:
Check the height
h = 192(60)
h = 11,520 ft