Mathematics 9709 · AS & A Level · Quadratics

Quadratics — practice question

The curve is defined by the equation $y = 4x^2 + 20x + 6$.
(a)[3]

Write the equation in the form $y = a(x + b)^2 + c$, with $a$, $b$ and $c$ as constants.

(b)[3]

Hence solve for $x$ in $4x^2 + 20x + 6 = 45$.

(c)[3]

Sketch the graph of $y = 4x^2 + 20x + 6$ and show the coordinates of the stationary point. You do not need to show where the curve meets the $x$- and $y$-axes.

Worked solution & mark scheme

This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: Correct coefficient is $a=4$

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI