64-х=91:7

To solve the equation 64 - x = 91/7, we can first simplify the right side by dividing 91 by 7:

91/7 = 13

Now, the equation becomes:

64 - x = 13

To isolate x, we need to subtract 64 from both sides of the equation:

64 - 64 - x = 13 - 64

This simplifies to:

-x = -51

Finally, we can solve for x by multiplying both sides of the equation by -1:

(-1)(-x) = (-1)(-51)

This yields:

x = 51

Therefore, the solution to the equation 64 - x = 91/7 is x = 51.