a ladder 7.5m long is leaning against a wall if the foot of the ladder is 3m from the wall how far up the wall does the ladder reach to reach the nearest metres

The change in water level of a lake is modeled by a polynomial function, w(x). described how to find the x-intercepts of w(x) and how to construct a rough graph of w(x) so that the parks department can predict when there will be no chage in the water level. you may create a sample polynomial of degree 3 or higher to use in your explanations.