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The trajectory of a ball thrown from a height of 160 meters is given by the equation
\[
y = 160 - \frac{x^2}{40}
\]
until it hits the water, where \( y \) is the height of the ball above the water and \( x \) is the horizontal distance traveled in meters.
Find the distance traveled by the ball from the time it is thrown until it hits the water.
