Imaginary Square Roots

If b²-4ac is negative, the quadratic equation has:

• Two real solutions that are different

• Two imaginary solutions that are different

• A real double solution

• An imaginary double solution

Solve.   x² = √-36

• x = ± 6

• x = 6i

• x = ± 6i

• x = i√6

Solve    x² = √-25

• x = -5

• x = ± 5i

• x = √5

• x = ± 5

Solve.   x² = √-90

• x = 3√10

• x = 9i√10

• x = ± 3√10

• x = ± 3i√10

the square root √-25 is..

• 5

• -5

• 8

• none of the above

√-4

• -2

• -2i

• 4

• 2i

• 2i

• -2i

• 2

• 4i

3√-81

• -27

• 3i√3

• 27i

• 9i

Solve.
  x² = √-100

• x = 10i

• x = ± 10i

• x = ±10

• x = √10