Question

If the lines x + 2y = 9, 3x – 5y = 5 and ax + by = 1 are concurrent, then the line 5x + 2y – 1 = 0 passes through the point

(a)  (b,a)

(b)  (a,b)

(c)  (-a,b)

(d)  (-a, -b)

Answer 1

Correct option  (B)  (a, b)

Explanation :

 The point of intersection of the lines x + 2y – 9 = 0 and 3x – 5y - 5 = 0 is (5, 2) which also lies on the line ax + by = 1. Hence

a(5) + b(2) = 1

5a + 2b = 1

 Therefore, the line 5x + 2y = 1 passes through the point (a, b).