Solving Quadratics by Completing the Square

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 - 20x + 98 = 0

• x = -10 ± √2

• x = 10 ± √2

• x = 2 ± √10

• x = -2 ± √10

What is one of the solutions to this equation?
(2x - 1)² = 49

• 7

• -7

• -4

• -3

x² + 10x = -9

• 1 and -12

• -1 and -9

• 1 and -9

• 1 and -1

Solve the equation by completing the square and then finding the roots. 
x²+ 6x - 4 = 36

• x = -7, 7

• x = 4, -10

• x = -4 +- √7

• x = 10, -4

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

What do you do to the b value to correctly complete the square?

• square it

• divide it by 2 and square the result

• divide it by 2 and take the square root of the result

• divide it by 2 only

Solve by completing the square.
x² +12x = 5

• X = 6 + √41 or  6 − √41

• X= 35 or 47

• X = −6 + √41 or  −6 − √41

• X = √35 or √47

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