Determine the quadratic function f(x) = ax^2 + bx whose graph passes through the point (2,9) and has a horizontal tangent at x = −1.

]supplementary angles are two angles that add up to . • complementary angles are two angles that add up to degrees. • adjacent angles share a and a • congruent angles have the measure. • an triangle has one angle that is greater than 90 degrees. • a triangle with angles 45°, 45°, and 90° would be a triangle