The correct question is
<span>Rui is a professional deep water free diver. His altitude (in meters relative to sea level), xxx seconds after diving, is modeled by: d(x)=1/2x^2 -10x What is the lowest altitude Rui will reach?
we have that
</span>d(x)=(1/2)x² -10x
we know that
the function is quadratic (a parabola)
so
<span>the lowest altitude (depth) is the vertex
</span>
using a graph tool
see the attached figure
the vertex is the point (10,-50)
that means
His altitude (in meters relative to sea level), 10 seconds after diving is 50 meters under the sea level
therefore
the answer is
<span>the lowest altitude is 50 meters under the sea level</span>
<span>Rui is a professional deep water free diver. His altitude (in meters relative to sea level), xxx seconds after diving, is modeled by: d(x)=1/2x^2 -10x What is the lowest altitude Rui will reach?
we have that
</span>d(x)=(1/2)x² -10x
we know that
the function is quadratic (a parabola)
so
<span>the lowest altitude (depth) is the vertex
</span>
using a graph tool
see the attached figure
the vertex is the point (10,-50)
that means
His altitude (in meters relative to sea level), 10 seconds after diving is 50 meters under the sea level
therefore
the answer is
<span>the lowest altitude is 50 meters under the sea level</span>