How to solve a quadratic equation by completing the square
Examples, solutions, videos, activities and worksheets that are suitable for A Level Maths.
What is Completing the Square?
Completing the square is a process to convert a quadratic equation from
the general form y = ax2 + bx + c
to the vertex form y = a(x - h)2 + k
The vertex form can be used to find the vertex of a quadratic equation and to solve a quadratic equation.
The following diagram gives the vertex form of a quadratic equation. Scroll down the page for more examples and solutions.
Completing the Square (Tutorial 1)
Completing the Square (Tutorial 2)
Completing the Square (Tutorial 3)
How to Solve a Quadratic Equation by Completing the Square?
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