# A bridge

A bridge over a river is in the shape of the arc of a circle with each base of the bridge at the river's edge. At the center of the river, the bridge is 10 feet above the water. At 27 feet from the edge of the river, the bridge is 9 feet above the water. How wide is the river?

Result

a =  80 ft

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THE BRIDGE OVER THE RIVER Dr Math
r = radius of circle of arc

x = distance between center of circle and water level (center of the circle is under ground)

y = distance in horiznotal of point on circle which is 9 ft above the water #### To solve this example are needed these knowledge from mathematics:

Looking for help with calculating roots of a quadratic equation? Do you have a system of equations and looking for calculator system of linear equations? Pythagorean theorem is the base for the right triangle calculator. See also our trigonometric triangle calculator.

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