The addition and subtraction of scores is mainly about the total score. The method of the total score is relatively simple, but there are often problems such as missing multiplication and forgetting to change symbols in the process of the total score. Therefore, on the basis of mastering the method, you must be careful in the process of doing the problem.

It is better to do more questions ~!

In the red circle, there will be total division. The first step of general division is to use the basic properties of fractions to make the denominators the same, so the denominators in the questions all become 2(x+2)(x-2).

For example, the denominator of the previous formula is (x+2)(x-2). If it becomes 2(x+2)(x-2), it must be multiplied by 2, so in order to keep the value of the fraction unchanged, the denominator must also be multiplied by 2.