what is the answer for the question?

Answer:
What I think the answer is is distributive property because you do x times 10, that makes 10x and if you do x times 4, it makes 4x. You can add 10x + 4x because they both have the x as the variable.
Step-by-step explanation:
(4+10)x You do x times 10 to get 10x, and you do x times 4 to get 4x.
4x + 10x = 14x