2. Wang Jing asked the teacher's age, and the teacher smiled and said, "The sum of our two ages is 565,438+0, and my age is three times smaller than yours, 65,438+0." Can you find out their ages with what you have learned? ( )

A. 13 years old and 38 years old B. 14 years old and 37 years old.

C. 15 and 36 years old D. 12 and 39 years old.

On Sunday, Xiaohong and her classmates walked to the countryside for an outing at a speed of 5 kilometers per hour. After leaving 16 minutes, mom found Xiaohong didn't bring her camera, so mom chased Xiaohong by bike at 13 kilometers per hour. How long will it take her to deliver the camera to Xiaohong ()?

A. 10 hour b.hour c.hour D.6 hour

Fill in the blanks (3 points for each question, 33 points)

1. Fill in the brackets the reason why the obtained equation holds:

(1) by ()

(2) By ()

2. if the equation is a linear equation about x, then m, the solution of this equation is.

3. If it is the solution of the equation, then a=.

4. If the values of are opposite to each other, the value of x is.

5. Xinghua Shopping Mall 1 1 day offers a 20% discount. Then the goods priced in 5 yuan will be priced in RMB;

The price of goods sold in 80 yuan is RMB.

6. No interest tax is levied on education savings, and the annual interest rate is 2.7%. Xiao Liang's parents took part in the education savings to prepare for Liang Xiao's college tuition five years later. How much money should Xiao Liang's parents save to get 5,000 yuan after the expiration of five years? It is required to set the unknowns and list the corresponding equations.

7. If x =–1is the solution of equation x+a=3, then a=.

8. The tenth digit is A and the second digit is B according to the formula.

Third, solve the following equation: (4 points for each question, 16 points)

1.2x+3x+4x+ 18 = 0 ^ 2。 4x-3=3x-4

3. 1/2x+2 = 1/3- 1 4。 20%+ 1=80%-5