What is the solution to the equation 13×3/4+x=7(1/4)

I'm going to assume you mean:

13 * (3/4) + x = 7 * (1/4)

Let's go ahead and simplify the right side.

7 * (1/4) = 1.75

So now we have:

13 * (3/4) + x = 1.75

Now let's take care of the right side. Multiplication before addition.

13 * (3/4) = 9.75

9.75 + x = 1.75

To isolate x, we subtract 9.75 from both sides.

9.75 - 9.75 + x = 1.75 - 9.75

x = -8

Hopefully I spaced this well. \('-')/