completing the square

American  

noun

Mathematics.

1. a method, usually of solving quadratic equations, by which a quadratic expression, as x 2 − 4 x + 3, is written as the sum or difference of a perfect square and a constant, x 2 − 4 x + 4 + 3 − 4 = (x − 2) 2 − 1, by addition and subtraction of appropriate constant terms.

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Example Sentences

But they often misremember it — the usual derivation is a bit convoluted, involving a technique called “completing the square” — and get the wrong answers.

From Seattle Times

They must be able to take a quadratic equation or an equation of a circle in whatever form and convert it, perhaps by completing the square, to a form so that they can analyze the graph.”

From Washington Post

Solve by three methods—formula, factoring, and completing the square: Review equations in the quadratic form and solve: 2.

From Project Gutenberg

Completing the square, to the south and west stretched a chain of oak posts set close together and pierced, as were the other walls of the stockade, by numerous portholes.

From Project Gutenberg