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How to solve the equation and find the equivalence relation in the first grade of mathematics
General methods for solving linear equations with one variable;

1, denominator

2. Remove the bracket

3. Mobile projects,

4. Merge similar projects

5. The coefficient is 1.

Step 6 check

For example, solve equation (3x-7)÷5= 16.

Solution: (3x-7)÷5= 16

3x-7= 16×5

3x-7=80

3x=87

x=29

Check:

left =(3×29-7)÷5 =(87-7)÷5 = 80÷5 = 16。

Right = 16

Left = right

So x=29 is the solution of the original equation.

Expand the data 1, master mathematical terms and find equivalence relations.

Quantitative relationship in practical problems: general sum-difference relationship or multiple relationship, which is often expressed by terms such as "one * * * has", "greater than ……", "less than …" and "several times more than ……". When solving problems, you can find the equivalence relation by grasping these terms, and list the equations in narrative order.

For example, "the school has carried out tree planting activities, and planted 50 trees in the fifth grade, four fewer than in the fourth grade." How many trees were planted in the fourth grade? " The key word of this question is "less than …", from which we can find the equivalence relation: 2 times the number of trees planted in the fourth grade minus 4 equals the number of trees planted in the fifth grade, thus listing the equation 2-4 = 50.

2. Find the equivalence relation according to the common quantitative relation.

Common quantitative relationship: working efficiency × working time = total workload; Unit price × quantity = total price; Speed × time = distance ... When solving problems, we can find equivalence relations according to these quantitative relations.

For example: "The retail price of a certain style of clothes is 36 yuan 1 set, and the current price is 2 16 yuan. A * * *, how many sets of clothes can I buy? " According to the quantitative relationship of "unit price × quantity = total price", equation 36 = 2 16 can be listed.