Correct Answer - Option 3 :
x ≥ y
Given:
x2 - 20x + 91 = 0
y2 + 6y - 91 = 0
Calculation:
From I,
x2 - 20x + 91 = 0
⇒ x2 - 13x - 7x + 91 = 0
⇒ x(x - 13) - 7(x - 13) = 0
⇒ (x - 7)(x - 13) = 0
⇒ x = 7, 13
From II,
y2 + 6y - 91 = 0
⇒ y2 + 13y - 7y - 91 = 0
⇒ y(y + 13) - 7(y + 13) = 0
⇒ (y + 13)(y - 7) = 0
⇒ y = -13, 7
Comparison between x and y (via Tabulation):
Value of x
|
Value of y
|
Relation
|
7
|
-13
|
x > y
|
7
|
7
|
x = y
|
13
|
-13
|
x > y
|
13
|
7
|
x > y
|
∴ x ≥ y.