Question

A roller coaster begins at 90 feet above ground level. Then it descends 105 feet. What is the height of the coaster after the first descent?

Answer 1

There are 2 ways of righting this:

Method 1: height is 15 feet below ground level

Method 2: height is -15 feet ( a negative value )

Explanation:

Drawing a sketch helps in understanding the question:

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Distance of travel is more than height above ground. So it ends up below ground (presume in a cut out).

Distance below ground is `105-90 = 15" feet"`

There are 2 ways of righting this:

Method 1: height is 15 feet below ground level

Method 2: height is -15 feet ( a negative value )