Diagnostic Test 3 Practice Test

$$ 6(3x - 5) + 4 = 2(3x - 5) + 24 $$

What is the value of $3x - 5$?

$$ 4x - 3y = 10 $$

$$ 12x + ky = 30 $$

In the system of equations above, $k$ is a constant. If the system has infinitely many solutions, what is the value of $k$?