Completing Square

What is the first step to solve this quadratic equation by completing square?  $x^2-10x+21\ =\ 0$  

• Set the equation equal to zero

• Add  $x^2$  and  $10x$  together

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

• Subtract the 21 on both sides

Tags

CCSS.HSA-REI.B.4B

What is the formula of calculate the new C-term

• C = $\frac{b}{2}$

• C = $\frac{-b}{2a}$

• C = $\left(\frac{b}{2}\right)^2$

• C = $\left(\frac{b}{4}\right)^2$

Tags

CCSS.HSA-REI.B.4B

Find the new C-term to create a perfect square trinomial
 $x^2+6x+_{ }$ ___

• 6

• -6

• 9

• -9

Find the new C-term to create a perfect square trinomial
 $x^2-4x+$  ___

• 4

• -4

• 16

• -16

Tags

CCSS.HSA-REI.B.4B

When factoring  $x^2-10x+25\ =\ 49$  
what goes into the blank   $\left(x-\ldots\right)^2=49$  

• 5

• 10

• 7

• 25

Tags

CCSS.HSA-REI.B.4B

What did you need to add to both sides to complete the square?

  $x^2-12x+_{ }$  ___ =  20 + ___

• 6

• 36

• 10

• 144

Tags

CCSS.HSA-REI.B.4B

What are the solutions to this quadratic equation  $\left(x-3\right)^2=16$  

• {7, 1}

• {4, -4}

• {3}

• {7, -1}

Write the following quadratic equation in completed square form $x^{2\ }+8x\ +2\ =\ 0\$  

•  $\left(x+16\right)^{2\ }=\ 18$  

•  $\left(x+4\right)^2=18$  

•  $\left(x+4\right)^2=14$  

•  $\left(x+2\right)^2=2$  

 what are the two equations of $\left(x+1\right)^2=9$ 

• x + 1 = 3  and  x + 1 = - 3

• x + 1 = 9  and  x + 1 = - 9 

Did you watch the video named 'Completing Square'?