Quadratic equations (Edexcel GCSE Maths): Flashcards

Equation where highest power of variable is 2

$ax^2 + bx + c = 0$ where $a \neq 0$

Factorise the left-hand side

Set each factor equal to zero

Solve the two linear equations

If two factors multiply to zero, one must be zero

Two solutions

Multiply to constant term, add to coefficient of $x$

When there is no constant term in the equation

$x^2 - a^2 = (x-a)(x+a)$

Add constant to both sides, then take square root

Both positive and negative squared give same result

Expand the brackets