Lines ax + by + c = 0 and 3a + 2b + 4c = 0 a,b,c∈R are concurrent at the point.
(3, 2)
(2, 4)
(3, 4)
(3/4, 1/2)
3a+2b+4c=0
⇒ 34a+12b+c=0
⇒ax+by+c passes through (3/4, 1/2) for all values of a, b, c.