Cut off a rectangle 2cm wide from the square sheet, and the remaining area is 48cm2. Then the area of the original square sheet is () A. 9cm2B. 68cm2C. 8cm2D. 64cm2
Let the side length of the square be xcm. According to the meaning of the question, we get x (X-2) = 48, and the solution is X1 = - 6 (rounding off), X2 = 8. Then the area of the original square iron sheet is 8 × 8 = 64cm2
RELATED INFORMATIONS
- 1. Arrange 1, - 1 / 2, 1 / 3, - 1 / 4, 1 / 5, - 1 / 6 according to certain rules in the following table First line 1 Second line - 1 / 2 1 / 3 The third line - 1 / 4 1 / 5 - 1 / 6 .. The seventh number from left to right in line 199 is () please give me some ideas
- 2. -(negative) the number represented by a must be a negative number B positive number C positive number or negative number d or above
- 3. Xiao Hong read a story book. She read 20 pages on the first day, 30 pages on the second day, and 5 / 8 of the book in two days. How many pages are there in this book?
- 4. A passenger car and a freight car leave from a and B at the same time, and meet in 4 hours. The freight car travels 50 kilometers per hour, and it takes 9 hours for the passenger car to complete the whole journey How many kilometers are there between the two places?
- 5. The original speed of a big car is 30 km / h, now it starts to accelerate evenly, increasing speed by 20 km / h The original driving speed of a large car is 30 km / h, now it starts to accelerate evenly, increasing the speed by 20 km / h; the original driving speed of a small car is 90 km / h, now it starts to decelerate evenly, decelerating by 10 km / h. how long does it take for the two cars to speed up equally? What is the speed at this time? (writing process)
- 6. The diameter of a car's outer tire is 9 decimeters, and the wheels roll 1000 cycles per minute. How long does this car advance per hour?
- 7. The speed of the car is 70km / h from a to B which is 360km away. Suppose the travel time of the car is t (H), and the distance from B is s (km) The vehicle is driven from a to B with a speed of 70km / h and a distance of 360km. Suppose that the travel time of the vehicle is t (H) and the distance to B is s (km). (1) the function of s with respect to t is written;
- 8. A and B trains leave 1050km apart from each other at the same time. A runs 80km per hour. After 2.8 hours, when the two trains are far away from each other, B runs now A and B trains leave 1050km apart at the same time. A trains 80km per hour. After 2.8 hours, the two trains are three fifths of the distance. How many kilometers per hour does a train travel?
- 9. The fruit shop has 1800 kg of apples. After 15 days of selling, the weight of the remaining apples is 60% of the weight of pears. How many kg of pears does the fruit shop have?
- 10. Given the supply voltage of 220 V sine AC circuit, the current in the circuit is 10 A, and the active power consumption is 1.5 kW?
- 11. There is a 96cm long and 36cm wide rectangular piece of paper. If you want to cut it into a square piece of paper with the length of the whole centimeter and the same area, you can cut several pieces
- 12. The area of a rectangle 96cm long and 36cm wide is six times that of a square. Find the side length of the square
- 13. It is known that the side length of a square is ACM. If the side length of the square is reduced by 3cm, how many cm is the area reduced
- 14. A square has an area of 49 square centimeters. What's its perimeter? What's its length and width?
- 15. The sum of the length and width of a rectangle is 80 cm. Its perimeter is equal to that of a square. What is the area of the square?
- 16. The length and width of a rectangle are increased by 4cm, and the area is increased by 80cm
- 17. The sum of the length and width of a rectangle is 80 cm. Its perimeter is equal to that of a square. What is the area of the square?
- 18. The bottom of a triangle is 10 cm, and its area is 80 square cm. How much should the bottom be shortened to reduce its area by 20 cm
- 19. The bottom of a triangle is 10 centimeters, and its area is 80 square centimeters. How many centimeters should the bottom be shortened to reduce its area by 20 square centimeters?
- 20. If a circle with a diameter of 8 cm is reduced by 2 cm, its perimeter and area will be reduced by () cm and () cm respectively