Describe the process of completing the square.

Completing the square is a method used to rewrite a quadratic expression in a standard form.

To complete the square, we start with a quadratic expression in the form of ax^2 + bx + c. We then take half of the coefficient of x, square it, and add it to both sides of the equation. This creates a perfect square trinomial on the left-hand side of the equation.

For example, let's say we have the quadratic expression x^2 + 6x + 5. We take half of the coefficient of x, which is 3, and square it, which gives us 9. We then add 9 to both sides of the equation:

x^2 + 6x + 9 = -5 + 9

On the left-hand side, we now have a perfect square trinomial, which can be factored as (x + 3)^2. On the right-hand side, we simplify to get:

(x + 3)^2 = 4

Finally, we take the square root of both sides of the equation, remembering to include both the positive and negative square roots:

x + 3 = ±2

We then solve for x by subtracting 3 from both sides:

x = -3 ± 2

So the solutions to the original quadratic equation are x = -1 and x = -5.

Completing the square is a useful method for solving quadratic equations, as it allows us to rewrite the equation in a standard form that is easy to factor or solve using the quadratic formula. It is also used in other areas of mathematics, such as calculus and differential equations.

Study and Practice for Free

Trusted by 100,000+ Students Worldwide

Achieve Top Grades in your Exams with our Free Resources.

Practice Questions, Study Notes, and Past Exam Papers for all Subjects!

Need help from an expert?

4.93/5 based on546 reviews

The world’s top online tutoring provider trusted by students, parents, and schools globally.

Related Maths a-level Answers

    Read All Answers
    Loading...