Question

Help please!!! I don't understand this!! Can you please show me how to do this??

Answer 1

x*2+4=0
x*2=-4
x=do root of -4
  can't possible to do root of -4

Answer 2

x² + 4 = 0
     - 4  - 4
       x² = -4
       x = 2i

x² - 6x + 7 = 0
x = -(-6) +/- √((-6)² - 4(1)(7))
                     2(1)
x = 6 +/- √(36 - 28)
                 2
x = 6 +/- √(8)
            2
x = 6 +/- 2√(2)
             2
x = 3 + √(2)
x = 3 + √(2)      x = 3 - √(2)