1. Factor out any number/variable that appears in all terms. For example, 4x2 + 16x - 20 = 4(x2 + 4x - 5)
2. If there the equation starts with just x2 (not 3x2 or -5x2), then you can factor it the "easy way" (See my YouTube video for worked examples)
3. If you couldn't do step 2 because there IS a number in front of x2, then you have to factor it with decomposition (see this YouTube video)
4. If neither Step 2 or Step 3 worked, then the equation may not be factorable. If the equation asked you to factor, you can just say "Not factorable" or "Does not factor". If you NEED to know the x-intercepts, you can use the quadratic formula.
Method to factor quadratic expressions:
1. Factor out any number/variable that appears in all terms. For example, 4x2 + 16x - 20 = 4(x2 + 4x - 5)
2. If there the equation starts with just x2 (not 3x2 or -5x2), then you can factor it the "easy way" (See my YouTube video for worked examples)
3. If you couldn't do step 2 because there IS a number in front of x2, then you have to factor it with decomposition (see this YouTube video)
4. If neither Step 2 or Step 3 worked, then the equation may not be factorable. If the equation asked you to factor, you can just say "Not factorable" or "Does not factor". If you NEED to know the x-intercepts, you can use the quadratic formula.
If you want more practice factoring, visit http://www.ontariosecondary.com/factoring.html. Each of those are factorable (I promise this time!)