Completing the Square

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

What value of c would make this a perfect sqaure trinomial?
x² +8x + c

• 4
• 16
• 64
• -16

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

• 4
• 2
• 8
• 20

 $x^2+6x-4=0$ 

Complete the Square. Do not solve!

•  $\left(x+3\right)^2=13$  

•  $\left(x-3\right)^2=-5$  

•  $\left(x+3\right)^2=5$  

•  $\left(x-3\right)^2=13$  

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}

 $x^2-12x-5=0$  Solve by completing the square.

• X = 6 + √41 or 6 − √41

• X= 35 or 47

• X = −6 + √41 or −6 − √41

• X = √35 or √47

 $x^2+9x+3=0$  Complete the Square

•  $x=-4\pm\sqrt{13}$  

•  $\left(x+4\right)^2=13$  

•  $x=4\pm\sqrt{13}$  

•  $x=\sqrt{13}+4$  

 $x^2-18x+4=0$  Complete the Square and Solve for "x."

•  $x=9\pm\sqrt{77}$  

•  $x=\sqrt{77}+9$  

•  $\left(x+9\right)^2=77$  

•  $x=-9\pm\sqrt{77}$  

 $x^2+16x-8=0$  Complete the Square. Do not Solve!

•  $\left(x-8\right)^2=72$  

•  $\left(x+8\right)^2=64$  

•  $\left(x+8\right)^2=-72$  

•  $\left(x+8\right)^2=72$  

 $x^2-10x-5=0$  Complete the Square and Solve for "x."

•  $x=-5\pm\sqrt{30}$  

•  $x=5\pm\sqrt{30}$  

•  $x=5\pm\sqrt{20}$  

•  $x=-5\pm\sqrt{20}$