Quadratic Formula and Imaginary Solutions

if a = 2, b = 4 and c = 10,  what are the errors in

 $\frac{4\ \pm\sqrt{16\ -\ 4\left(2\right)\left(-10\right)}}{2}$  

• The 4 outside the radical should be negative.

• The denominator should be 4, not 2.

• 10 should be positive and not negative.
  
  

• All of the above

Simplify √-4

• 2i
• -2i
• 2
• 4i

Solve x² - 5x + 10 = 0

• (5 - i√15)/2  ,  (5 + i√15)/2
• (5 - √15)/2  ,  (5 + √15)/2
• (5 - i√65)/2  ,  (5 + i√65)/2
• (5 - √65)/2  ,  (5 + √65)/2

Solve -2x² + 4x = 9

• (2 - i√14)/2   ,   (2 + i√14)/2
• (2 - i√-56)/2   ,   (2 + i√-56)/2
• (2 - i√-14)/2   ,   (2 + i√-14)/2
• (2 - √14)/2   ,   (2 + √14)/2

Solve using the Quadratic Formula.

 $x^{2\ }-6x+10=0$  

•  $x=-4,\ 4$  

•  $x=3+i,\ 3-i$  

•  $x=3i,\ -3i$  

•  $x=-3,\ 3$