Question 824088
A plane is currently at 200 ft and its descending at 10 ft per minute. The path of the gliding plane can be given by the following equation, 
y=-10x+200 
where y is the height of the plane and x is the number of minutes. 
In how many minutes will the plane land?
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y is zero when the plane lands.
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Solve: -10x + 200 = 0
-10x = -200
x = 20 minutes 
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Cheers,
Stan H.
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