Complete the Square

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 equation by completing the square:
n² - 2n - 3 = 0

• {3, -1}
• {4, -4}
• {5, -3}
• {8, -7}

Solve the following equation by completing the square:
n² = 18n + 40

• {11, -11}
• {16, 2}
• {20, -2}
• {10, -4}

Solve by completing the square:
k² − 12k + 23 = 0

• {6 + √13, 6 - √13}
• {-6 + √13, -6 - √13}
• {6 + √59, 6 - √59}
• {-6 + √59, -6 - √59}

Solve the equation by completing the square: 7x² - 14x - 56 = 0

• -6 and 12

• -2 and 4

• 4 only

• 3∓√10

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

Convert the perfect square trinomial into a binomial squared: x² + 16x + 64

• (x+8)²
• (x-8)²
• (x-4)²
• (x+4)²

Convert the perfect square trinomial into a binomial squared: x² + 14x + 49

• (x+7)²
• (x+7)(x-7)
• (x-7)²
• (x+14)²

To solve by completing the square, what needs to be moved in this equation?
x² = 9 - 4x

• the -4x
• the 9
• the x²

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

• 4
• 2
• 8
• 20