Question

4.
If x² = y2 + xy = 1 and x + y = 2, then find xy
(A) - 3
-3
(C)
2
(B) 3
(D) does not exist​

Answer 1

Answer:

( B ) 3

Step-by-step explanation:

x+y = 2 -------- (i)

x²+y² + xy = 1

x²+ y² +2xy - y

(x + y)² - xy = 1

From equation (i)

(2)² - xy = 1

4 - xy = 1

- xy = 1 - 4

- xy = -3

xy = 3