Rui is a professional deep water free diver.His altitude (in meters relative to sea level), x seconds after diving, is modeled by:d(x)=21x2−10xWhat is the lowest altitude Rui will reach?□ meters relative to sea level
Q. Rui is a professional deep water free diver.His altitude (in meters relative to sea level), x seconds after diving, is modeled by:d(x)=21x2−10xWhat is the lowest altitude Rui will reach?□ meters relative to sea level
Identify Quadratic Equation: Identify the quadratic equation that models Rui's altitude.The given equation is d(x)=(21)x2−10x.Here, a=21, b=−10, and c=0, since there is no constant term.
Find Vertex Time: Find the x-coordinate of the vertex of the parabola, which will give us the time at which Rui reaches his lowest altitude.The x-coordinate of the vertex of a parabola given by ax2+bx+c is found using the formula x=−2ab.Substitute a=21 and b=−10 into the formula.x=−2∗(21)−10x=110x=10
Calculate Lowest Altitude: Calculate the lowest altitude Rui will reach by substituting the x-coordinate of the vertex into the original equation.d(x)=(21)x2−10xd(10)=(21)(10)2−10(10)d(10)=(21)(100)−100d(10)=50−100d(10)=−50
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