I'm having a bit of trouble with this question, all it says is '2k = 26'

2k=26

To find this get k by itself and to do so get rid of the numbers on it's side.

To do so do the opposite of the symbol

Ex: when adding, subtract it from both sides.

Ex when dividing multiply both sides

Now to solve this

Divide 2 from both sides which gives the answer

K=13

6

Step-by-step explanation:

This is a case of combination since the order does not matter, it only matters that there must be a marble in each one inside, therefore we must apply its formula.

xCn = n! / x! * (n - x)!

n, in this case it would be 4 because we must subtract 2 from the total 6, since there must already be one inside in each display case.

x = 2, since it is the number of showcases.

Replacing:

 2C4 = 4! / 2! * (4 - 2)! = 6

Which means that you can in six different ways.