Answer:
Both A and B
Step-by-step explanation:
r² - 2r = - 5
r² - 2r + 5 = 0
Here,
a = 1
b = - 2
c = 5
D = b² - 4ac
= ( - 2 )² - 4 ( 1 ) ( 5 )
= 4 - 20
D = - 16
r = - b ± √D
= - ( - 2 ) ± √-16
= 4 + √-16, 4 - √-16
= 4 + √- 4, 4 - √- 4
r = √- 4 + 4, - √- 4 + 4
