Solve Quadratic by Completing the Square

Solve: x² - 2x = 3

(just give the POSITIVE answer)

Mathematical Equivalence

OFF

• A
• B
• C
• D

What is the first step to solving THIS equation by completing the square?
a² + 10a + 21 = 0

• Set the equation equal to zero

• Divide 10 by 2 and add the result to both sides

• Add a² and 10a together

• Subtract the 21

Solve the following quadratics equation by completing the square...

x² - 10x - 5 = 0

• x = -5 ± √30

• x = 5 ± √30

• x = 30 ± √5

• x = -30 ± √5

Solve the following quadratics equation by completing the square...

x² + 6x - 3 = 0

When factoring
x² - 4x + 4 = 20,
what goes in the blank?
(x - __ )² = 20

• 4

• 2

• 8

• 20

When do you use the plus or minus symbol?
±

• After taking the square root of both sides

• After adding the square to both sides

• After taking half of b

• After setting the equation equal to zero

Write the following quadratic expression in completed square form...

x² + 6x = 5

• (x + 3)² = 5

• (x + 6)² = 9

• (x + 3)² = 14

• (x + 6)² = 14

Write the following quadratic expression in completed square form... x² + 4x + 10

• (x + 4)² + 6

• (x + 2)² + 6

• (x + 4)² - 6

• (x + 2)² - 6

How many solutions are there?

• 0

• 1

• 2

• Cannot be determined