The first principle is to look for the meaning of each operation. For example, divisor = dividend/quotient, 9. The principle is that both sides of the equation expand or shrink by the same multiple at the same time. The equation remains unchanged (both sides increase or decrease the same number at the same time). It should be noted that expansion and contraction (increase or decrease) should be simultaneous. 0, the book says it is the principle of balance, but it is actually the property of the equation. Pay attention to the simultaneous addition (or subtraction, multiplication, division) of both sides of the equation when doing the problem. When you multiply and divide, you have to multiply and divide every term in the equation. 0, there are two principles: 1. The properties of the equation, the left and right sides of the equation are added and subtracted at the same time or the two sides are expanded or reduced by the same multiple at the same time, and the equation remains unchanged.
2. According to the meaning of operation, such as product = factor * factor, divisor = dividend/quotient, 0, the principle of solving the equation is to find the root of the equation, that is, the specific value.
What we should pay attention to is that sometimes we have to check whether the root we seek conforms to the equation. 0, if both sides are multiplied or divided by a number, the equation remains the same, 0, and you can still see 0 when you come back,