Answer:
The answer is A. x= 1/2k
Explanation:
1. collect like terms
4kx+10kx=7
14kx=7
2. divide both sides by 14k
14kx/14k=7/14k
that takes out 14k from the left side and you are left with x and then you have x=7/14k which can be simplified to 1/2k
x=1/2k