9. A birdhouse sits on top of a pole. A wire attached 3 ft below the top of the pole is attached to an anchor which is 12 ft from the bottom of the pole. If the hypotenuse of the right triangle formed by the pole, wire, and ground is 18 ft long, find the height of the pole. Round your answer to one place.
10. The hypotenuse of a right triangle is 6 ft longer than the shortest side. If the sum of the lengths of the two legs is 21 ft, find the lengths of all three sides.
11. Find the equation of the axis of symmetry for the parabola given by y = x2 + x – 12.
12. Find the equation of the axis of symmetry for the parabola given by y = x2 + 15x.
14. Find the coordinates of the vertex for the parabola given by f(x) = x2 – 2x.
15. Find the coordinates of the vertex for the parabola given by y = 2x2 + 8x + 11.