There s a math problem. Everybody answers!

ao=bo, so angular oba=angular oab

And because ab cd, so angular oba = angular odc; Angular OAB = Angular OCD (Intramisaligned Angle).

So the angle oba = angle oab = angle odc = angle ocd so, od = oc, and because angle boc = angle aod (to the apex angle) so, triangle boc = triangle aod (sas) so ad=bc

So. Trapezoidal ABCD is an isosceles trapezoidal shape.

Bring a=24 into b=2a-10.

b = 38 so a 24 cm shoe is a size 38.

5mm = so the scale of this juxtaposition is 1:4

It is more appropriate to choose a line chart.

Time is constant, and distance is proportional to speed.

Survival rate of one shift: 42 50 = 84%.

Survival rate of the second shift: 36 40 = 90%.

Therefore, the survival rate of class 2 is high.

v=sh= r Zen Bridge h=108 339

So qualified. I didn't understand this question-

15) Increasing it by 1/5 is answering the omission 18

The reciprocal of the fraction A is 5/6, and the fractional unit of A is (1 5). A plus (4) of these fractional units is the smallest prime number.

It is known that a b is a non-zero natural number, a+b = 35, the maximum value of a+5b is (171), and the minimum value of rot is (39).

Solution: A takes 48 (48-40) = 6 (hours) from A to B 48x6 = 288 (kilometers to return to Heye) Answer: A and B are 288 kilometers apart.

If there is only one equation for preparing for hunger, it is: 48x[48 (48-40)].

The invariant quantity (other trees or non-willows) is treated as a unit 1 by the method of transformation.

Think: "The number of willow trees is 2/5 of the total number of trees", that is, willows account for 2 (5-2) = 2 3;"In this way, 5/11 of all trees", that is, willows make up 5 (11-5) = 5 6 of all other trees.

This is the case for other trees.

50 (5 6-2 3) = 300 trees.

The original willow was.

300*2 3=200 or 300*5 6-50=200 trees.

If there are x trees in the park, then there are 2 5*x willow trees(2 5*x+50) (x+50)=5 11x=875

Solution: Set the original willow trees as x and the total number of trees as y, then get from the question:

x=y2/5 →5x=2y

This year, another 50 trees were planted, so according to the title, x+50)=(y+50)5 11 11(x+50)=5(y+50)

Solve these two equations.

x=200 (tree).

So there were originally 200 willow trees in People's Park.

Let the total number of trees be x, then the original number of willows in the People's Park is 2/5 x, and after planting 50 willows, the number of willows in the People's Park becomes 2/5 x plus 50, and the total number of trees will also increase after the willow trees increase, so the total number of trees becomes x+50 and the equation of the total number of willow trees after planting 50 willow trees to obtain: 2/5 x+50 divided by x+50 is equal to 11/5. is the equation for the relationship between willows and the total number of trees, and the equation is (2 5x+50) (x+50)=5 11

x=500 So 2 5x=200 People's Park originally had 200 willow trees. Hope it helps.

Solution: If the total number of trees is x, then the number of willow trees is 2 5x;

Equation: 2 5x+50=(x+50)·5 1122 25x+110=x+50

The total number of x = 500 trees is 500 and the number of willow trees is 200 + 50 = 250.

Hope it helps!

After planting willow trees this year, there are 50 (5 11) = 110 (trees).

The original willow trees in People's Park 110-50 = 60 (trees) Answer:

Let it be that there is x

Original total = 5x 2

x+50）/（5x/2+50）=5/11x=200

Set the original x willow trees.

x+50) (5 2*x+50)=5 11 or set a total of x trees.

2/5*x+50)/(5/2*x+50)=5/11

Factory A has 100 tons of steel in stock, and 15 tons are used every day, and Factory B has 82 tons of steel in stock, and 9 tons are used every month

100-15x=82-9x

15x-9x=100-82

6x=18x=3The price of a certain commodity is 120 yuan, and if the price is reduced by 9%, it can still make a profit of 20 ...... relative to the purchase priceThe purchase price of this item is 88 yuan.

Solution: Set the purchase price to X yuan.

x+20=120×

x+20=108

x=88 Algebraic formula 2a+1 and 1+2a are inverses to each other, then a=

2a+1+1+2a=0

4a = -2a = if 2m+1 of 5 times the square of b and m+3 of half the square b of -half a are homogeneous, then m = 7

1/3(2m+1)=1/2(m+3)

2(2m+1)=3(m+3)

4m+2=3m+9

m=7 Knowing that the trapezoidal lower base is 6 cm, the height is 5 cm, and the area is 25 square centimeters, then the length of the upper bottom is 4 cm

Solution: Set the top bottom to x cm.

6+x)*5/2=25

6+x)*5=50

6+x=10

x=4 to forge a cylindrical blank with a diameter of 16cm and a height of 5 cm, and to cut off a square steel x cm with a variable length of 6 cm, the equation can be 6*6x= *8*8*5

The radius is 16 2 = 8 cm.

6*6x=π*8*8*5

Let y1 = 1/5 x + 1, y2 = 2/4 x + 1, when x is what is the value, y1 and y2 are opposite to each other (equation) solution.

x+1)/5+(2x+1)/4=0

4(x+1)+5(2x+1)=0

4x+4+10x+5=0

14x=-9

x=-9/14

(1) 100-15x=82-9x=3 (2) Set the purchase price to x 120*90%=x+20 x=88 (3)2a+1+1+2a=0 a= (4) I didn't understand this question.

5) Set the length of the upper bottom xcm, (6+x)5=25 x=4(6)16 *5=6x

7) y1, y2 are inverse numbers, so x+1+2x+1/4 = 0 x = minus 20/7

Please be clear ...

How do you find the square of a circle? This question is to first find the volume of the rough to be forged (you wrote it wrong). Then divide by 6 on the square and you're good to go.

7.That is to say, one-fifth x+1 is equal to 2x+4/1 to find x

You misunderstood! Let's calculate it this way: the preferential payment per person is 2 3 + 25 3, and if it is +1 yuan, it is 10 yuan.

Each person actually only needs to pay 25 3 yuan, and the remaining 2 3 yuan and 1 yuan go into the pockets of the waiter and himself, respectively.

Some of your 9 yuan was paid to the waiter, so it's overcounted. As for the undercounting, just use the above method!

You 27 out of 27 undercounted the money returned.

3*9+2=Is this a miscalculation**?

Wrong, of course. It should be 3*9-2=25 yuan, that is, the boss gets 25 yuan for a total of 30 yuan, the boss gets 25 yuan, the waiter gets 2 yuan, and the three people get 1 yuan each.

Classic topic, the use of the concept of stealing.

Don't follow his train of thought.

Look at this: each of them gave 9 yuan, 3*9=27. Of the 27 yuan, 25 yuan is at the boss and 2 yuan is at the waiter. That's it.

The three of them didn't give 30 dollars! I only gave 27 yuan, but it was only 25 yuan.

If there is a logical error in the latter part of the question, the correct one should be:

Room fee 25 yuan + waiter secretly hid 2 yuan = 3 people, 9 yuan per person, a total of 27 yuan.

Solution: (8 8) (12 8) = 2 3

Set the height to x cm

5-x）（12×8）=8×8x

480-96x=64x

160x=480

x=33cm=

Water is high in decimeters. Please, thank you!

It can be solved by a series of equations, let the unfinished is x meters, and the completed is x + 50 meters, please see ** for the detailed process.

Solution: Mu Huai set up female workers Xun Qinyou has a person.

There are A+162 male workers in the first ear.

a+162）×（1-1/11）=（a-12）×25a+810=11a-132

6a=942

a=157

.Is the number of remaining male workers twice as many as the remaining female workers, or...

If the number of female employees is x, then the number of male employees is 162+x

From the meaning of the question, it can be obtained that (162+x)*10 11=2*(x-12) can be obtained x=157

So there are 157 female workers in this factory.