Converting Quadratics: Standard Form and Vertex Form
Learn how to convert a quadratic between standard form (also called general form) and vertex form. Let's get started! 🚀

Video Lesson
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Flashcards
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🛎️ What are Standard Form and Vertex Form?
- Standard (general) form:
- Vertex form:
🛎️ Converting Vertex Form to Standard Form
- Expand the square using , then expand the brackets
- Don't forget the constant at the end (this is a very common mistake)
🛎️ Converting Standard Form to Vertex Form
- Only factor out from the and terms. Ignore the constant
- E.g.
🛎️ Completing the Square
- When completing the square, anything added inside must be undone outside
- E.g.
Practice Questions
Test your understanding
Convert the quadratic equation into general form.
Correct! 🎉 +10 pointsNot quite right
To convert from vertex form to general form, start by expanding to get . Then, distribute the 3 to each term: . Finally, subtract the 4 outside the brackets: . Simplifying, we get .
Convert the quadratic equation into general form.
Correct! 🎉 +10 pointsNot quite right
To convert from vertex form to general form, start by expanding to get . Then, distribute the 4 to each term: . Finally, add the 2 outside the brackets: . Simplifying, we get .
Convert the quadratic equation into vertex form.
Correct! 🎉 +20 pointsNot quite right
To convert to vertex form, we complete the square. We want to turn into a perfect square. Take half of 4, which is 2, then square it: . Now we have . But since we added 4, we need to subtract it to keep the expression balanced: . So the equation becomes .
Convert the quadratic equation into vertex form.
Correct! 🎉 +20 pointsNot quite right
First, complete the square: take half of -6 (which is -3), then square -3 to get 9. Now, rewrite the equation as . We added 9 inside the brackets to complete the square, so we must subtract 9 to keep the equation balanced. After simplifying, we get .
Convert the quadratic equation into vertex form.
Correct! 🎉 +20 pointsNot quite right
First complete the square: take half of -8 (which is -4), then square -4 to get 16. Now, rewrite the equation as . We added 16 inside the brackets to complete the square, so we must subtract 16 to keep the equation balanced. After simplifying, we get .
Convert the quadratic equation into vertex form.
Correct! 🎉 +30 pointsNot quite right
First, factor out the 3 from the and terms: . Next, complete the square inside the brackets. Half of -4 is -2, and squaring -2 gives 4. Now, rewrite the equation as . We added 4 inside the brackets, so we subtract outside to keep the equation balanced. Simplifying, we get .
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