4) A right triangle is constructed by taking a point (x, y) on the graph of the function f(x) = vx, drawing a line vertically downward to the x-axis, then connecting both of those points to the origin as in the picture below. Denote the length of the base of the triangle by x, the height of the triangle by y (in meters), and the Area of the triangle by A. When x = 9 m (and only at that moment), the height y is shrinking at a rate of 5 m/min. Find the value of |dA dt J x=9m w ( x, y ) 2 2 3 4 Solve the problem by performing the following steps. a) (1 point) Find a formula for the height, y, of the triangle as a function of x. (This is denoted as y(x).) y (x ) = b) (4 points) Find the value of dx dt J x=9m dx ] Jx=9m c) (2 points) Find a formula for the area, A, of the triangle as a function of x. (This is denoted as A(x).) A ( x ) = d) (4 points) Find the value of [dA] at JX=9m dA Jx=9m e) (4 points) Write a sentence to explain what the value found in (d) means about the triangle. (Don't forget UNITS.)