Tim Gan Math
Sign up free

Sketching from the general form by completing the square

Sketching from the general form by completing the square

Secondary 3
  1. Express \(-x^2-4x+1\) in the form \(-(x+p)^2+q\).
  2. Hence sketch the graph of \(y=-x^2-4x+1\), showing the turning point and the points where the graph meets the axes. Give the \(x\)-intercepts correct to 3 significant figures.

Solution:

Solution locked

680+ questions here come with free worked solutions. A free account saves your questions and progress; this one needs a course plan.

Create free accountSign inGet the E Math course · from S$29.98/moE Math tuition

Create a free account to practise similar questions.

Create free accountSign inGet the E Math course · from S$29.98/moE Math tuition
Answer:(i) \(-(x+2)^2+5\) (ii) Maximum point \((-2,5)\); \(y\)-intercept \((0,1)\); \(x\)-intercepts \((-2+\sqrt5,0)\approx(0.236,0)\) and \((-2-\sqrt5,0)\approx(-4.24,0)\)

Need help? Join our E-Maths tuition for O-Level success.

Learn more