UPSC NDA Math Model Paper 10

Here, (1, 2) is midpoint
∴ 1 = (0 + b)/2 ⇒ b = 2
Also, 2 = ( a + 0)/2 ⇒ a = 4
i.e., x-intercept = b = 2 and y- intercept = a = 4
∴ Equation of line = x/2 + y/4 =1
⇒ 2x + y = 4
Hence, option (3) is correct.