Maths & numbers

Complete the square from standard coefficients calculator

Recover the scale and shifts needed to write a quadratic as a square plus a constant.

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Behind the numbers

How this calculation works

Recover the scale and shifts needed to write a quadratic as a square plus a constant.

THE FORMULAax²+bx+c = a(x−h)²+k with h=−b/(2a) and k=c−b²/(4a)

A worked example

2x²−12x+17 becomes 2(x−3)²−1.

Good to know

The leading coefficient must be nonzero.

Read the result

Recover the scale and shifts needed to write a quadratic as a square plus a constant.

The primary result is labeled “Vertex shift h”. Keep the input definitions in view when comparing this result with another method.

Try a related calculation

The leading coefficient must be nonzero.

For a related exercise, try the quadratic equation solver.

A few questions, answered

How can I check the default inputs by hand?

2x²−12x+17 becomes 2(x−3)²−1.

Which rule does this calculator apply?

ax²+bx+c = a(x−h)²+k with h=−b/(2a) and k=c−b²/(4a)

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