Binary Equation Solving Process! Find the solution to a binary equation!

Solution: Consists of 1200+4y=500x

2400+20x=20y.

The solution is y=(500x-1200) 4=125x-300y=(2400+20x) 20=120+x, i.e., 125x-300=120+x

Get x = 105 31

Bringing x=105 31 into (1)1200+4y=500x gives y=3825 31

So x=105 31

y=3825/31

Both sides of equation (1) are divided by 4 at the same time, so.

300+y=125x (3)

Both sides of equation (2) are divided by 20 at the same time, so.

120+x=y (4)

Bring (4) into (3), so.

300+120+x=125x

124x=420

x=105/31

Bring x=105 31 into equation (4), so.

y=120+150/31

y=3825/31

x=105/31

y=3825/31

Are you sure you got a few numbers wrong?

Equation (2) is divided by the left and right at the same time to obtain: x-y=-120, that is, x=y-120 is substituted into (1) equation 1200+4y=500 (y-120) to obtain: 504y=7200

y=100/7

x=100/7-120=-740/7

1) multiplies the equation by 5 and adds equation (2) to become a unary equation: 2480x=8400, x is easy to get, and then substituting the value of x into either of the previous two equations can solve y....

Equation (1)*5 is obtained.

3)6000+20y=2500x

2) formula + (3) formula to obtain.

8400=2480x

x=105/31

y=3825/31

Room sheets. 1, (1) set to take x days.

1/20+1/x=1/12

x = 30 (2) x + 2 (1 - x 30) (1 20) no more than 35x minimum 15

1) Set up the arrangement to make shirts x people, pants (24-x) people.

3x=5(24-x)

x = 15 (2) 90x + 80 (24-x) not less than 2100 at least 18 workers need to be arranged to make shirts.

The price of each item is X yuan.

Sell (350-10a) items.

a-21)(350-10a)=400

A-21 no more than 21 5

a=25350-10a=100

1 (1) solution: It takes x days and the total project is 1, then: by the title: Team A does 1 20 per day alone, and 1 12 per day together

1/20+1/x=1/12

x=30 or let A do x every day and B do y every day, then:

12(x+y)=1

20x=1 gives x=1 20 and y=1 30

Team B takes 30 days to complete.

2) Set up team A day A and team B day B.

2a+b≤35

a/20+b/30=1

Assuming that the maximum is 350,000 yuan, the solution is b = 15, a = 10 Answer: Then the B engineering team will have to work for at least 15 days.

2 (1) arrange to make shirt x men, pants y men.

3x=5yx+y=24

Solution: x=15, y=9

2)90x+80y≥2100

x+y=24

Assuming that the minimum is 2100 yuan, the solution is: y=6, x=18A: At least 18 workers need to be arranged to make shirts.

3. Set the price of each product at a yuan, and you need to sell B products.

350-10a=b

ab-21b=400

a-21≤21*20％

Obtained by a, a=25, b=100, the condition is satisfied.

A: The store plans to earn 400 yuan, and needs to sell 100 items, each item costs 25 yuan.

These problems use the method of unary equations:

1, (1) set to take x days.

1/20+1/x=1/12

x = 30 (2) x + 2 (1 - x 30) (1 20) no more than 35x minimum 15

1) Set up the arrangement to make shirts x people, then the pants are (24-x) people.

Get: 3x=5(24-x).

Solution. x=15

2) 90x+80 (24-x) is not less than 2100, then the least. 90x+80(24-x)=2100 solution. x=18

A minimum of 18 workers are required to make the shirts.

The price of each item is a yuan.

Sell (350-10a) items.

a-21)(350-10a)=400

A-21 no more than 21 5

a=25350-10a=100

Solution 1: If half of the people who take the bus first take x kilometers and walk y kilometers, the time spent is x 20 + y 4 hours.

When the first half of the people get off the bus, the first half of the people have already walked x 5 km, and 4x 5 km is covered by people and cars together, and the time required is 4x 5 (4+20) = x 30 hours. When people and vehicles meet, the first walker walks a total of x 5 + 4 x 30 = x 3 km, and the remaining 2x 3 + y km rides. The time consumed is x 3 4+(2x 3+y) 20 hours.

So the equation is as follows:

x+y=100

x/20+y/4=x/3/4+(2x/3+y)/20

The simultaneous solution is x=75 and y=25.

Therefore, the time spent is 75 20 + 25 4 = 10 hours.

From this it can be seen that the troops set off at 7 o'clock in the morning.

If the distance walked by the person is x km, then the car repeats a round trip on the middle 100-2x distance, a total of 100 + 2 (100-2x) = 300-4x km. People and cars spend the same amount of time on the way, so there is.

x/4+(100-x)/20=(300-4x)/20

Solving this equation yields x = 25 km.

So the time spent is 25 4 + 75 20 = 10 hours.

From this it can be seen that the troops set off at 7 o'clock in the morning.

Set a train car can carry x tons of goods, and a car can carry y tons of goods 6x+15y=360

8x+10y=400 ②

Simplification to 2x+5y=120

Simplification to 4x+5y=200

We get 2x=80 so x=40 and x=40 substitut y=8

A: A train can carry 40 tons of cargo, and a car can carry 8 tons.

Binary once, ternary quaternary once, etc., are all converted into one yuan once, x 100 substituted into a formula to get y 150

(x+y) in the new system of equations is regarded as the original x, then x+y=7

(x-y) in the new system of equations is regarded as the original y, then x-y = 1

The solution is x=4 and y=3