Deriving the Quadratic Formula by Completing the Square

Deriving the Quadratic Formula by Completing the Square

Assessment

Interactive Video

Mathematics

9th - 10th Grade

Hard

Created by

Quizizz Content

FREE Resource

This video tutorial teaches how to derive the quadratic formula by completing the square. It begins with an introduction to quadratic expressions and their components, followed by a detailed explanation of factoring perfect square trinomials. The main focus is on the step-by-step derivation of the quadratic formula, highlighting key steps such as setting the equation to zero, dividing by 'a', and manipulating terms to complete the square. The tutorial concludes with the final quadratic formula, emphasizing the importance of understanding each step in the process.

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7 questions

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1.

MULTIPLE CHOICE QUESTION

30 sec • 1 pt

What are the values of a, b, and c in the expression 2x² + 5x + 8?

a = 1, b = 5, c = 8

a = 1, b = 6, c = 9

a = 2, b = 5, c = 8

a = 2, b = 6, c = 9

2.

MULTIPLE CHOICE QUESTION

30 sec • 1 pt

What is the first step in factoring a perfect square trinomial like x² + 12x + 36?

Take half of the b term and square it

Square the b term

Subtract the c term

Multiply the b term by 2

3.

MULTIPLE CHOICE QUESTION

30 sec • 1 pt

In the process of deriving the quadratic formula, what is done after setting the equation to zero?

Subtract b from both sides

Add c to both sides

Divide by a on both sides

Multiply by a on both sides

4.

MULTIPLE CHOICE QUESTION

30 sec • 1 pt

How do you find the new c term when completing the square in the quadratic formula derivation?

Add the b term to a

Multiply the b term by 2

Divide the b term by 2 and square it

Square the b term

5.

MULTIPLE CHOICE QUESTION

30 sec • 1 pt

What is the result of combining the fractions in the quadratic formula derivation?

b² + 4ac over 2a

b² - 4ac over 4a²

b² + 4ac over 4a²

b² - 4ac over 2a

6.

MULTIPLE CHOICE QUESTION

30 sec • 1 pt

What operation is performed to isolate x in the final steps of deriving the quadratic formula?

Multiply by 2a

Subtract b over 2a

Add b over 2a

Divide by 2a

7.

MULTIPLE CHOICE QUESTION

30 sec • 1 pt

What is the final form of the quadratic formula derived by completing the square?

x = b ± √(b² - 4ac) / 2a

x = -b ± √(b² - 4ac) / 2a

x = b ± √(b² + 4ac) / 2a

x = -b ± √(b² + 4ac) / 2a