Aunt Zhang and Aunt Li took the same amount of money to buy salt. They used all the money to buy Edible salt. Aunt Zhang took 8 bags and Aunt Li took 12 bags After returning home, Aunt Li supplied Aunt Zhang with 4 yuan. How much is each bag of edible salt?

Let Aunt Zhang and Aunt Li each carry X Yuan
(X-4)/8=(X+4)/12
The solution is x = 20 yuan
Each bag of edible salt (20-4) / 8 = 2 yuan

Auntie Zhang and auntie Li went shopping together. Auntie Zhang liked a dress and auntie Li liked a pair of shoes, but they didn't have enough money. If auntie Li lent money to Auntie Zhang to buy clothes, she had 50 yuan left. If Auntie Zhang lent money to auntie Li to buy shoes, she had 100 yuan left. The price of clothes was 1.5 times that of shoes, How much money did Aunt Zhang and Aunt Li take to the supermarket?

Let Aunt Zhang take X Yuan and Aunt Li take y yuan
Simultaneous equations; (X-100) * 1.5 = y-50
（x+y）-50=[（x+y）-100]*1.5
The solution is x = 120, y = 80, so Aunt Zhang brought 120 yuan and Aunt Li 80 yuan
How many brain cells did big brother die

Sine theorem, cosine theorem
In the acute triangle ABC, BC = 1, angle B = 2, angle a, then the value of AC / cosa =, the value range of AC is

Sine theorem of sina / BC = SINB / AC
SINB = sin2a = 2sinacosa angle doubling formula
therefore
sinA/1=2sinAcosA/AC
cosA/AC=1/2
AC/cosA=2
AC=2cosA
0

The inequality of solution about X: (1 / 2-A) x > 1-2a
2010.6.10, before 6:30. Forget it after time

(1/2-a)x>1-2a
1/2(1-2a)x-(1-2a)>0
(1-2a)(1/2x-1)>0
When a > 1 / 2, X

Draw the largest circle in a rectangle 8 cm long and 6 cm wide, and find the area and perimeter of the circle

The diameter of the largest circle is 6 cm
6 △ 2 = 3cm, radius
14 × 3 × 3 = 28.26 square centimeter. The area of the largest circle
14 × 6 = 18. 84 cm. The circumference of the largest circle

Triangle ABC is an isosceles triangle. The degree of vertex angle a is twice that of base angle B. what are angles a, B and C

Let angle B be x degree, because it is an isosceles triangle, so angle c is also X
Angle a is twice that of angle B, so angle a is 2x
X+X+2X=180
X = 45 degrees

F (x) is a function defined on R, and f (x + 2) = (1 + F (x)) / (1-f (x)) try to prove that f (x) is a periodic function
The answer is
f(x+4)=(1+f(x+2))/(1-f(x+2))=-1/f(x)
How do I get - 1 / F (x)?

f(x+2)=[1+f(x)]/[1-f(x)]
1+f(x+2)=1+[1+f(x)]/[1-f(x)]=2/[1-f(x)]
1-f(x+2)=1-[1+f(x)]/[1-f(x)]=-2f(x)/[1-f(x)]
So f (x + 4) = {2 / [1-f (x)]} / {- 2F (x) / [1-f (x)]} = - 1 / F (x)

After removing 6 decimeters from the length of a rectangle, the area will be reduced by 24 square decimeters. What is the width of the rectangle

1. The side area of a cylinder is 37.68 square decimeters, and the height is 2 decimeters. What's its volume
2. In a cube with an edge length of 10 cm, the volume of the largest cylinder is cut
3. What is the volume of a 3 cm high cylinder whose surface area is 18.84 square cm larger than its side area
4. The diameter of the front desk of a roller is 2m, and the width of the front desk is 3M. When the front wheel of the roller rotates 10 cycles per minute, how many square meters is the roller area per minute

1,37.68/2 = 18.84,18.84 / (2 * 3.14) = 3, Volume V = 3 * 3 * 3.14 * 2 = 56.522, cylinder diameter 10cm, height 10cm, Volume V = 5 * 5 * 3.14 * 10 = 785cm3; 3, bottom area = 18.84/2 = 9.42cm2, so volume v = 9.42 * 3 = 28.26cm3; 4, side area s = 2 * 3.14 * 3 = 18.84m2, compaction area = 18.84 * 10 =

Revise the exercises of sick sentences
1. We should make every effort to make our agriculture mechanization and collectivization
2. In the past, people only read their novels and seldom noticed their images
3. His ruddy face is like a pear blossom in full bloom
4. He was one of the survivors
5. With the development of society and the change of life, many words have changed

1. We should make every effort to make our agriculture mechanization and collectivization
2. In the past, people only read their novels and paid little attention to their images
3. His ruddy face is like a peach blossom in full bloom
4. He was one of the many survivors
5. With the development of society and the change of life, many words have changed

Aunt Zhang and Aunt Li took the same amount of money to buy salt. They used all the money to buy Edible salt. Aunt Zhang took 8 bags and Aunt Li took 12 bags After returning home, Aunt Li supplied Aunt Zhang with 4 yuan. How much is each bag of edible salt?