I want to ask for a junior high school math problem

Solution: Let the purchase price of the commodity be X yuan.

According to the title:

8000 (10%x)-6000 (20%x)=100 Solve this equation to get x 500

It has been tested that x 500 is the root of the original equation.

So x 500

8000 (10%x) 8000 (10*50%)=160A: The purchase price of this product is 500 yuan, and a total of 160 pieces are sold in the second month.

Solution: If the purchase price of the product is X yuan, the mall will sell Y pieces in the first month, and the second month will sell (Y + 100) pieces.

Binary Linear Equation Solution.

A: The mall sold a total of 160 pieces in the second month.

Set the purchase price of the product to be b yuan, and buy a product in the first month.

So: 20% b yuan per piece.

So: 20%BA=6000

10%b（a+100）= 8000 ②

By the deed, by the deed:

Substituting b = 500

Substituting b = 500 to get it.

a=60a+100=160

The purchase price of the goods is 500 yuan, and the mall sells a total of 160 pieces in the second month.

Set the purchase price to x, and sell y pieces in the first month.

20%xy=6000

10%x(y+100)=8000

Solution x = 500 yuan.

y=60, 60+100=160 pieces sold in the second month.

Let the x-yuan be lowered.

then the present tense is 2-x yuan.

The selling price is 2*(1+25%)

Now the gross profit margin is 25%+15%.

So (2-x)*(1+25%+15%) = 2*(1+25%)(2-x)*

2-x=x=so lowers the meta.

Price = 2 * (1 + 25%) = yuan.

Later cost = yuan.

Cost reduction :(

Connect AC to pass EF to m, from the meaning of the title: ae:eb=m:n, then df:fc=m:n, then ae:ab=m:(m+n).

cf:cd=n:(m+n) because ae:

ab=em:bc=m：（m+n），cf:

cd=mf:ad=n:(m+n), so em=bc*m (m+n),mf=ad*n (m+n), add em and mf together to get it, as for the median formula, let m:

n=1 is enough, you can get it.

God, it's so tiring to switch typing.

From the meaning of the title: ae:eb=m:n, then df:fc=m:n, then ae:ab=m:(m+n).

cf:cd=n:(m+n) because ae:

ab=em:bc=m：（m+n），cf:

cd=mf:ad=n:(m+n), so em=bc*m (m+n),mf=ad*n (m+n), add em and mf together to get it, as for the median formula, let m:

n=1, that's it!

Solution: From the sum without quadratic terms, we can know that a=-4 b=6 so the sum is -10x-15y

Without quadratic terms, the coefficient before x and xy is 0

So a=4, b=6

So the sum of the polynomials is -10x-15y

There are three scenarios for this question:

1.The side length 2 corresponds to the side length 4, then the ratio is 1 2, and the side lengths of the triangle frame corresponding to the side length 5 and side length 6 are 5 2 and 3, respectively;

2.The side length 2 corresponds to the side length 5, then the ratio is 2 5, and the side length 4 and side length 6 correspond to the side length of the triangle frame is 8 5 and 12 5 respectively

3.The side length 2 corresponds to the side length 6, then the ratio is 1 3, and the side length 4 and side length 5 correspond to the side length of the triangle frame is 4 3 and 2 respectively.

1.Select, 3 for the other two sides.

2. Choose 8 5 and 12 5 for the other two sides.

3.Choose 4 3 and 5 3 for the other two sides.

Note: The key to this kind of issue is to discuss it in a categorical manner, and it should be considered comprehensively.

Answer: The other two sides of another triangular frame are of length.

and 3 or and or 2 3 and 4 3

Choose 3 and draw on the other two sides.

Or choose 4 out of 3 and 5 out of 3

Yuan m 3> Yuan m 3, water consumption exceeds 10 cubic meters, and the excess part is x cubic meters.

10 times x = 4 Total water use is 14 cubic meters.

If the water used in March is x cubic meters, it will be x yuan.

x = 14 Mr. Wang's family used 14 cubic meters of water in March.

Set the water consumption in March x cubic meters.

10* +x-10)* = 1 * x

x = 14