If x^2 + y^2 = 9 and xy = 8, then x + y is equal to

If x² + y² = 9 and xy = 8, then x + y is equal to
(a) 25
(b) 5
(c) -5
(d) ±5

Solution:

If x + = 2, then x² + is equal to
(a) 4
(b) 2
(c) 0
(d) none of these

Solution:

(102)² – (98)² is equal to
(a) 200
(b) 400
(c) 600
(d) 800

Solution:

More Solutions:

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