Question 92

If x + y = 12 and $$x^2 + y^2$$ = 94, then xy is

Solution

Given : $$(x + y) = 12$$ and $$x^2 + y^2 = 94$$

Using $$(x + y)^2 = x^2 + y^2 + 2xy$$

=> $$(12)^2 = 94 + (2 \times xy)$$

=> $$2 xy = 144 - 94 = 50$$

=> $$xy = \frac{50}{2} = 25$$

=> Ans - (A)

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