![](data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 72 71" width="72"></svg>)
Application of solving linear equation of one variable 1. Xiao Ming and Xiao Dong each have a number of extra-curricular books. The number of extra-curricular books of Xiao Ming is twice that of Xiao Dong. After Xiao Ming gave Xiao Dong 10 books, the number of extra-curricular books of Xiao Dong is three times that of Xiao Ming's remaining. How many extra-curricular books did Xiao Ming and Xiao Dong have? 2. The purchase price of a product is 2000 yuan, and the price is 3000 yuan. The store requires a discount of 5% of the profit. How much discount should the salesman give?
One yuan a time!
1. If Xiaodong had x copies, Xiaoming would have 2x copies
Xiaoming has 2x-10 copies and Xiaodong has x + 10 copies
So we have the equation x + 10 = 3 * (2x-10)
It can be solved that x = 8, that is, Xiaodong originally had 8 books
Xiaoming has 2 * 8 = 16 books
2. To make a profit of 5% is to make a profit of 2000 * 5% = 100 yuan
In this way, the selling price of 2100 yuan can meet the requirements
Then the discount is 2100 / 3000 = 0.7, that is, 7% off to sell the product!
RELATED INFORMATIONS
- 1. It is known that, as shown in the figure below, in the trapezoidal ABCD, ad is parallel to BC, ad = 24cm, BC = 30cm, and point P moves from point a to D at a speed of 1cm / s, Stop at point D. point Q moves at a speed of 2cm / s from point C to point B, and stops at point B. the truncated trapezoid of line PQ is two quadrilaterals. When P.Q starts at the same time, a few seconds later, one of the quadrilaterals is a parallelogram?
- 2. Mathematicians help me to solve the square root formula: X (n + 1) = xn + (A / xn &; xn) 1 / 2. What is the subscript of X on the left side of the equal sign
- 3. In the diamond ABCD with side length of 6, if ∠ ADC = 120 °, P is the upper moving point of AC and E is the middle point of BC, then the minimum value of Pb + PE is___
- 4. How to write English in kindergarten
- 5. Use 11 squares with a perimeter of 8 decimeters to form a rectangle. What is the perimeter and area of the rectangle?
- 6. It takes 26 seconds for a train to pass the 396 meter bridge and 18 seconds to pass the 252 meter tunnel. How long is the train's body?
- 7. If the quadrilateral ABCD is a square and the triangle EBC is an equilateral triangle, then the degree of angle X is () degrees
- 8. The taxi charge standard of a city is: the starting price is 3 km 5 yuan, more than 3 km, 1 km plus 1 yuan during the day; after 10 pm, 1.2 yuan per km At 22:15, Aunt Wang took a taxi to the fire station for a total of 7.8 kilometers. How much should Aunt Wang pay?
- 9. In the quadrilateral ABCD, EF divides AB into three equal parts and Mn divides DC into three equal parts
- 10. Help me look at some math problems! It's a process (2xy-y) - (- y + YX) =? 5 (a squared b-3ab squared) - 2 (a squared b-7ab squared) =? First simplify, then evaluate (4a + 3a square-3 + 3A cube) - (- A + 4A cube), where a = - 2: 1 2X squared y-2xy squared - [(- 3x squared y squared + 3x squared y) + (3x squared y squared - 3xy squared)] Where x = - 1, y = 2
- 11. A right angled trapezoid, the sum of the top and bottom is 18 cm, and the two waists are 4 cm and 6 cm long respectively. How many square centimeters is the area of this trapezoid?
- 12. A = 9, B = - 8, then what are the numbers of 2003 power of a plus 2004 power of B? (it should be 5) please explain the reason
- 13. If you sell a certain commodity at a fixed price, you can make a profit of 40 yuan for each commodity. If you sell it at a 20% reduction, you will lose 20 yuan for each commodity. What is the purchase price of this commodity emergency
- 14. Use "+" - "to connect numbers 3, 20, 5 and 12 to form a formula. Can the result of this formula be 24? If not, please explain the reason; if yes, please write this formula. What if" 5 "is changed to" 6 "? Note that you can only use + - Oh, other words seem to be very good, but you can only use + - oh
- 15. The original price of a kind of camera is 574 yuan, which has been reduced by 3 / 9. Now the price of the camera is? Yuan, and the car runs 60 km per minute on a section of road Two fifths of the length. How long is this highway In the first day and the second day, 80 parts were finished, and in the third day, 2 / 9 of these parts were finished. How many parts are there in this batch The original price of one kind of camera is 574 yuan. After the price has been reduced by 3 / 9, the current price is? Yuan A section of road, the car 45 branches of 60 kilometers per minute, this section of road is two fifths of the length, how long is this section of road In the first day and the second day, 80 parts were finished, and in the third day, 2 / 9 of these parts were finished. How many parts are there in this batch
- 16. It is known that the line L: y = x, the ellipse C center is at the origin, the focus is on the x-axis, the focal length is 2, and the short axis length is 2 √ 3 (1) The left focus of ellipse C is F1, the right vertex is B, and the parallel line L 'of straight line L passing through point F1. If l' intersects ellipse C with m and N, calculate the area of triangle MNB
- 17. It is known that the center of the ellipse with eccentricity of 4 / 5 is at the origin and the focus is on the x-axis. The focal length of the hyperbola with the major axis of the ellipse as the real axis and the minor axis as the imaginary axis is 2 √ 34 (1) Solving the equation of ellipse and hyperbola (2) Let the left and right vertices of the ellipse be a and B respectively, take a point P on the hyperbola in the second quadrant, connect BP intersection ellipse to point m, connect PA and extend the intersection ellipse to point n. if BM (vector) = MP (vector), calculate the area of the quadrilateral anbm
- 18. It is known that the center of the ellipse is at the origin, the focus is on the y-axis, the focal length is 4, and the eccentricity is 2 / 3, It is known that the sum of the distances from a point on the ellipse with the focus on the x-axis and the center on the origin to the two focuses is 4. If the root of the eccentricity of the ellipse is 3 / 2, then the equation of the ellipse is
- 19. It is known that the center of the ellipse is at the origin, the focus is on the y-axis, the focal length is 4, and the eccentricity is 2 / 3
- 20. Suppose that the center of the ellipse is at the origin o, the focus is on the X axis, the eccentricity is (√ 2) / 2, and the sum of the distances from one point P to two focuses on the ellipse is equal to √ 6. (1) if the straight line x + y + m = 0 intersects the ellipse at two points a and B, and OA ⊥ ob, find the value of M?