If 52 x equals 7800 y what does 1 x equal? what is the maths equation?

You gave the equation right at the beginning.  It's [ 52 x = 7,800 y ].

As you requested, I'll proceed now to solve your equation for 'x'.
I'll go slowly, and explain each step clearly.  Please try to follow
along with my procedure.

Step #1:
Write down the equation:     52 x = 7,800 y

Step #2:
Divide each side of the equation by 52 :    x = 7,800 y / 52

Step #3:
Perform the division indicated by the fraction, and underline the answer.

                  x = 150 y