L

Quadratic Equations

Equations

  • Quadratic equations can be written in the form ax^2 + bx + c = 0 where a,b and c are numbers
  • You need to be able to solve a quadratic equation without using your calculator
    • Rearrange it into the form ax^2 + bx + c = 0
    • Factorise the left-hand side
    • Set each factor equal to zero and solve to find two values of x

Worked it out

  • Follow the three steps given above
  • The equation is already in the right form sometimes
  • To factorise look for two numbers which add up to the 2nd number and multiply to make the 3rd number
  • Set each factor equal to 0 and solve
  • When you are solving a quadratic equation you must rearrange it into the form
  • Be really careful if the coefficient of x^2 is bigger than 1
    • When you are solving an equation`you must always show clear algebraic working
    • Don’t just write down the answers without any working