In the coordinate plane, line \(k\) passes through the origin and has slope \(2.\) If points \((3,y)\) and \((x,4)\) are

[Vincen]

In the coordinate plane, line \(k\) passes through the origin and has slope \(2.\) If points \((3,y)\) and \((x,4)\) are on line \(k,\) then \(x+y =\)

(A) 3.5
(B) 7
(C) 8
(D) 10
(E) 14

Answer: C

Source: Official Guide