For a certain value of k, the system
3a + 4b = 7
6a + 4b = k + 3a
has infinitely many solutions (a,b). What is k?
The answer is k = 5.
Subtracting 3a from the second equation gives us \(3a + 4b = k\) and \(3a + 3b = 7\)
For the system to have an infinite amount of solutions, they must be the same line.
Can you take it from here?