1, the value of x below is the equation 2x- 1=7, and the solution is .............................................. (IV).

a、x= 1 B、x=2 C、x=3 D、x=4

2. In the following four equations, ......................................... (b) takes x= -3 as the solution.

a、3x-7=2 B、4x+ 10=x+ 1 C、5x=2-x D、6x+8= -26

3. If the algebraic expression 2x- 1 has a value of 5, then the value of x is ....................................... (IV).

a 、-2 B、2 C 、-3 D、3

4. If x=4 is the solution of equation 2a+ 1=5-2x, then the value of a is ............................ (III).

a 、-6 B 、-4 C 、-2 D、5

Class 5.7 (1) held a philatelic exhibition. The number of stamps on display is 24 more than the average of 3 per person and 26 less than the average of 4 per person. The number of stamps displayed in this class is .................................. (IV).

a、 164 B、 178 C、 168 D、 174

Second, concentrate on filling in.

6. The solution of equation 5x= 10 is (X=2).

7. If -3x2a- 1+6 = 0 is a linear equation, then a=( 0.5).

8. Please write a linear equation with one variable whose solution is x=5: (X+ 1=6).

9. When x=( 5), the value of the algebraic expression 3x- 1 is 3 larger than the value of 2x+ 1.

10, Li Hong bought eight wheat cakes in a wheat cake shop, paid 50 yuan and brought them back to 2 yuan. Let the price of each wheat cake be x yuan. According to the meaning, the equation is (8X=50-2).

1 1. If a 20 cm long iron wire is made into a rectangle more than 2 cm long, the length of the rectangle is (6) cm.

12. A test paper has only 25 multiple-choice questions. If you answer a question correctly, you will get 4 points, and if you do a wrong question, you will be deducted. If a student does all the papers, he will get 70 points, and then he will answer (20).

13, the basic price of living in a certain place is 0.50 yuan/degree. It is stipulated that the basic electricity consumption per month is one kilowatt hour, and the electricity price per kilowatt hour exceeds the basic electricity consumption by 20%. If a user spends 100 kWh in May and pays the electricity bill to 56 yuan, then a=( 40) kWh.

(1) it is known that the two equations 5x-4=3x about x have the same solution as ax- 12=0, so the value of a is found. ..

Solving equation: (5x-4=3x)

Solve this equation and get (X=2).

Substitute ax- 12=0 to get 2a= 12 a=6.

(2) It is known that x= 1 is the root of equation 2x-m-1 =0, and the algebraic expression 1(-4m? +2m-8

The value of).

X= 1 is substituted into 2x-m-1 =0, and 2-m=4 and m=-2 are obtained.

Substitution algebraic expression =(- 16-4-8)/4=-7.

Fourth, the application questions

(1) An eco-food processing factory in Yongjia purchased a batch of mountain products with the mass of 1000 kg, and roughed and finished it according to the market demand. As we all know, the quality of refined mountain products is three times that of roughing mountain products, which is 2000kg more, so we need to roughing the quality of mountain products.

Solution: Set (rough machining quality is x)

Solve the equation: (X+3X+200= 1000)

Solve this equation to get (X=200).

Mountain products mass of rough machining = 200kg.