Answer:
Explanation:
D is the discriminant of the quadratic equation on left. It tells you how many solutions there are.
D=negative >2 imaginary/complex solutions
If D is negative, you can never get negative under a square root so you get imaginary numbers
D=0 >1 real solution
If D is 0, the ± goes away so you only have 1 solution
D = positive >2 real solutions
If D is positive, then you get 2 real solutions.
Solution:
(A) x² + 6x + 9
a=1
b=6
c=9
D = b² - 4ac
D = 6² - 4(1)(9)
D = 36 - 36
D = 0 >From explanation above 1 real solution
(B) x² +2x +3
a=1
b=2
c=3
D = b² - 4ac
D = 2² - 4(1)(3)
D = 4 -12
D = -8 >negative, from above 2 imaginary/complex solutions