Two ferry boats start at the same instant on opposite sides of the river. one is faster than the other. they cross at a point 720 yards from the left shore on their way to their respective destinations, where each one spends 10 minutes to change passengers before the return trip. they meet again at a point 400 yards from the right shore. how wide is the river?

First locate the turning point (vertex) of the graph. which is at the coordinates x=5 and y=9 or (5; 9).to determine whether it's a maximum or mininum value, you have to discern whether the vertex's y-value is the highest value or lowest value the graph can reach. since the vertex's y-value, 9 is the highest value the graph can reach, it will be a maximum.another basic way to determine whether the vertex's value is max or min is to see if the graph is smiling or sad. if it's smiling, the turning point/vertex would be a minimum, while a sad parabola would have a maximum y-value at the vertex.

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The answer is 1040 because the zeros arent significant