Week 5 Day 2: Solving Quadratics

Week 5 Day 2: Solving Quadratics

Solving By Factoring

Solving by Factoring Example

Multiple Choice

Use the zero product property to solve the equation.

 $x^2-2x-15=0$  

• x = -2 or x = -15

• x = -3 or x = 5

• x = -5 or x = 3

• x = -2 or x = 3

Multiple Choice

Use the zero product property to solve the equation.

 $2x^2-6x+4=0$  

• x = 2 or x = 8

• x = 1 or x = 2

• x = -2 or x = 2

• x = 2 or x = 4

Multiple Choice

Use the zero product property to solve the equation.

 $5x^2-9x-2=0$  

• x= $-\frac{1}{5}$ or x = 2

•  $x=5\ \ \ \ or\ \ \ \ x=-2$  
  

• x = -1 or x = 2

• x = -5 or x = $\frac{1}{2}$

Solving Using Square Roots

Solving Using Square Root Example

Example 1

Example 2

Example 3

Multiple Choice

Solve  $\left(x+1\right)^2-8=\ 0\ \$  using square roots.

• x =  $\sqrt{8}$  

• x = 0

• x =  $1\ -\sqrt{8}$    or  x=  $1\ +\sqrt{8}$  

• x =  $-1\ -\ 2\sqrt{2}$    or  x=  $-1+2\sqrt{2}$  

Multiple Choice

Solve  $\left(x-2\right)^2=\ 9\ \$  using square roots.

• x = -1  or  x= 5

• x = -3  or  x= 3

• x = 5

• x = 1

Multiple Choice

Solve  $7x^2+5\ =19\ \$  using square roots.

• x = -2  or  x= 2

• x =  $-\sqrt{2}$    or  x=  $\sqrt{2}$  

• x =  $-\sqrt{14}$    or  x=  $\sqrt{14}$  

• x = -14  or  x= 14

Multiple Choice

Solve x² + 4 = 68 using square roots.

• x = -8 or x= 8

• x = $-\sqrt{72}$ or x = $\sqrt{72}$

• x = $-6\sqrt{2}$ or x = $6\sqrt{2}$

• x = $-\sqrt{68}$ or x = $\sqrt{68}$

Multiple Choice

Solve 3x² = 12 using square roots.

• x = -2 or x = 2

• x = 2

• x = $-\sqrt{12}$ or x = $\sqrt{12}$

• x = -4 or x = 4

Solve Using the Quadratic Formula

Solving Using the Quadratic Formula Example

Example 1

Example 2

Multiple Choice

Solve using the quadratic formula:

4x² + 4x + 1 = 0

• x = -½

• x = -2

• x = 0

• x = ½

Multiple Choice

Solve using the quadratic formula.
2x² - 9x - 35 = 0

• x = 7/2, x = -6
• x = -5/2, x =5
• x = -3/7, x =6
• x = -5/2, x = 7

Multiple Choice

Solve using the quadratic formula. 

 $x^2+2x+4=0$  

•  $x=-1$  

•  $x=1\ \ \ and\ \ \ x\ =\ i\sqrt{3}$  

•  $x\ =\ -1\ -\ i\sqrt{3}$  and  $x\ =\ -1\ +\ i\sqrt{3}$  

•  $x\ =\ 1\ -\ i\sqrt{3}$  and  $x\ =\ 1\ +\ i\sqrt{3}$