x=7/8- 1/2

x=3/8

x+5/ 12= 1/2

x= 1/2-5/ 12

x= 1/ 12

19/36-x=5/ 18

x= 19/36-5/ 18

x= 1/4

Adding (or subtracting) the same number or the same algebraic expression on both sides of the equation at the same time, the result is still an equation. Multiplied by the same number on both sides of the equation (or divided by the same non-zero number), the result is still an equation.

Extended data:

An equation must contain an equal sign, so an equation without an equal sign is not an equation; The equation must be an equation and contain unknowns, and both conditions must be met at the same time; This equation can contain several unknowns.

In order to find the unknown number, an equivalent relationship is established between the unknown number and the known number.

The sequence equation can be divided into two steps: the first step is to set the unknown according to the problem setting conditions; The second step is to find the equivalent relationship between the unknown and the known number, so as to get the equation.