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aizel28
Nov 28, 2007, 05:27 AM
I can't make any equation in this queastion:

1.two helicopters departed simultaneously from an airport. One flies due south; the other flies due east at the rate that is 70 km per hour faster than the first helicopter. After 1 h, the radar indicates that the helicopters are 170 km apart. What is the ground speed of each helicopter?:confused:

2.An L-shaped sidewalk from building A to building B in a college campus is 200 m long. By cutting diagonally across the grass, students shorten the walking distance to 150 m. What are the lengths of the two sides of existing sidewalk?:confused:

I hope you can help me.. thank you god bless.. :)

terryg752
Nov 28, 2007, 06:54 AM
1. Suppose speeds are x and x+70

After 1 hour, distance^2 = (Can you see the right angled triangle?)

x^2 + (x + 70)^2 = 170^2

Now you can determine values of x and x+70

2. Suppose lengths of the two sidewalks are x and (200 - x)

Just like part 1,

x^2 + (200 - x)^2 = 150^2

Now you can find values of x and (200 -x)