DIRECTIONS for the question:Solve the following question and mark the ...
Given equation x
2 + y
2 = 29 is a circle with radius
units and the given equation xy = 10 is a rectangular hyperbola. The graphs of these two equations are as follows.
Given x2 + y2 = 29 and xy = 10
► (x+y)2 = x2 + y2 +2xy = 49
► x + y = 7 or -7 → (i)
► (x-y)2 = x2 + y2 – 2xy = 9
► ∴ x – y = 3 or -3 → (ii)
Form (i) and (ii), we get
► (x, y) = (5,2) or (2,5) or (-5, -2) or (-2, -5).
Distance between (5, 2) or (2, 5) = Distance between (-5, -2) and (-2, -5) → (i)
Distance between (5, 2) and (-2, -5) = Distance between (-5, -2) and (2,5) → (ii)
As the pairs of opposite sides are equal and (ii) > (i), i.e., adjacent sides are not equal, the points of intersection can either form a rectangle or a parallelgram, but only rectangle is given in the options.
► Note: Even if the above graph cannot be visualized, the question can still be answered by solving the two equations.