Question

(Theoretical) If from O a point in AB two straight lines OC, OD are drawn onopposite sides of AB so as to make the angle COB equal to the angleAOD; show that OC and OD are in the same straight line.​
(based on Theorem)

Answer 1

3x – 7y = 10, xy = -1

3x -7y= 10

Squaring both sides,

(3x – 7y)2 = (10)2

⇒ (3x)2 + (7y)2 – 2 x 3x x 7y = 100

⇒  9X2 + 49y2 – 42xy = 100

⇒  9x2 + 49y2 – 42(-l) = 100

⇒ 9x2 + 49y2 + 42 = 100

∴ 9x2 + 49y2 = 100 – 42 = 58