To calculate the problem directly, you need to write "original formula =" without copying the problem. The original formula represents the above formula. If you are willing to copy the question again, you don't have to write the original formula.

This is a standard practice, just like writing an equal sign before calculating a problem. The process of finding the value of unknown x is called solving the equation, and writing the solution means that the later process is solving the equation.

For another example, when solving equations, the "=" of each step should be aligned up and down, which is also a norm. The purpose is to clearly see how each step of solving the equation is well practiced through reasonable rule changes. The posture of writing should be correct, and each stroke should be written straight enough, just like a straight line drawn with a ruler; For all horizontal strokes, it is stipulated that it must be slightly raised to the right, but the last big stroke cannot be raised again; Don't focus on the left and light on the right in horizontal strokes, like writing sketches or meteor lines; If there is a long horizontal picture in the middle of the font, boldly lengthen the width.