The graph of f(x) = 2x + 3 shifts 10 units to the right when it is replaced with the graph of f(x) = 2x − k. what is the value of k? 3 7 10 13

To shift a function to the right simply apply the idea of the parent function being f(x) and a horizontal (left and right) shift as being f(x- or + h) depending if left or right. 

TO the right function would be f(x-h), so f(x-10). plug in x-10 into x

f(x-10) = 2(x-10) + 3 = 2x - 20 + 3 = 2x - 17. So k should equal 17?

Then just do it (lol)