Solve for x: 2x^2 + 2x -24 = 0
- The general formula of a quadratic is ax^2 + bx + c -> this is a quadratic 2) Factorise using common factor (=2) -> 2(x^2 + x - 12) = 0 3) Factorise the quadratic to (x + m)(x + n): the two numbers (m and n) in each bracket ADD to make b and MULTIPLY to make c. Don't forget the common factor from step 2 -> 2(x-3)(x+4) = 0 4) Divide both side of equation by 2 -> (x-3)(x+4) = 0 5) Two values multiply to make '0', so this means either or both equal 0. So, if (x-3) = 0, then x = 3; if (x+4) = 0, then x = -4.
