Solution
Given : $$(x^2 + y^2) = 85$$ and $$xy = -18$$
Using $$(x + y)^2 = x^2 + y^2 + 2xy$$
=> $$(x + y)^2 = 85 + (2 \times -18)$$
=> $$(x + y)^2 = 85 - 36 = 49$$
=> $$(x + y) = \sqrt{49} = 7$$
=> Ans - (D)
Create a FREE account and get:
- Free SSC Study Material - 18000 Questions
- 230+ SSC previous papers with solutions PDF
- 100+ SSC Online Tests for Free
