GCSE Maths (Edexcel)

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The Quadratic Formula

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Algebra Solving Equations and Inequalities

The Quadratic Formula

6:29 More Quadratic Equations
Spec A18
Previous Advanced Solving by Factorisation Next Solving by Completing the Square
  • Quadratic equations can be solved using the quadratic formula
  • The quadratic formula is x = (-b �� ���(b^2 - 4ac)) / 2a
  • The quadratic formula gives up to two solutions to the equation
  • The positive and negative solutions are obtained by adding or subtracting the square root term
  • If the content of the square root is zero, there will be a repeated solution
  • If the content of the square root is negative, there will be no solution
  • To solve a quadratic equation using the quadratic formula, rearrange the equation to the form ax^2 + bx + c = 0
  • Identify the values of a, b, and c
  • Substitute the values into the quadratic formula and solve for x using a calculator
  • Round the solutions to two decimal places by looking at the third decimal place

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