A child stands at the bottom of a tall slide and throws a ball toward the top of the slide. The slide is modeled by the equation y=2x, and the path of the ball through the air is modeled by y=−x2+6x+1
where x is the horizontal distance and y is the vertical distance, both in feet. When the ball hits the slide, approximate how many feet off the ground it will be?

Round your answer to the nearest whole number.