For these questions to be true and the equation of the tangent to have an equal y to the equation of the parabola i guess there has to be a "c" and in that case integrate the equation of the tangent you will have a = 5 and b = -18 then you substitute in the equation of the parabola with the point you have you will find that "c" = 21 and so the equation of the parabola becomes y = 5x^2 - 18 x +21
