The system of two primary and one ternary equations must be calculated and solved

Is the first question y=2-7 written incorrectly, if yes, the answer:

Solution: y=2 7 yields y=-5

Substituting y=-5 into 5x+3y+2z=2 gives 5x+2z=17, and from 5x+2z=17, we get z=17 2-5 2x and substituting z=17 2-5 2x into 3x 4z=4 to get x=38 13, substituting x=38 13 into z=17 2-5 2x gives z=95 13 and gets x=38 13

y=-5z=95/13

Answer to the second question.

Solution: Multiply 3x+y+15z=18 by 2 to get 6x+2y+30z=36, subtract x+2y+3z=36 from 6x+2y+3z=2 to get 5x+27z=34

Get x=5y=1 3

z=1 3, substituting z=4 9z-17 9 into 3x+y+15z=18.

, substituting 5x+3y+2z=2 to get 5x+2z=17Get z=17-5x 2 substitution to get x=0, z=-1, (think slowly about the first question, the second question, hehe).

y=2 7 gives y=-5, and then substitutes 5x+3y+2z=2 to get 5x+2z=17, 3x 4z=4 2 yuan one-time equation can be connected by itself.

4x－9z=17

3x+y+15z=18

x+2y+3z=2

First of all, the three-formula x3 and the two-formula subtract and cancel x, and then it becomes a 2-element equation, you can solve y and z, and then substitute the z value into the equation to get the x value.

Solution: y=2-7

5x+3y+2z=2 ②

3x-4z=4 ③

Substituting into gets: 5x+6-21+2z=2 2 gets: 10x+12-42+4z=4

Get: 13x=38

x=38/13

Substituting x=38 13 yields: 190 13-21+2z=22z=23z=

y=-5The solution of this system of equations is: x=38 13

y=-5z=

a-b+c=0 to c=-a+b is substituted into the following two formulas.

4a+2b+c=3 is converted to 3a+3b=3, and a+b=1 is simplified.

25a+5b+c=60 is converted to 24a+6b=60, and 4a+b=10 is simplified.

A-B: 4a+b-(a+b)=15-3, simplified to a=3 and bring a=3 into the above formula in turn, to get a=3 b=-2 c=-5

The Liberation faction repents and withers:

y=x=50x=50

y=100 is well written, hard work, and hope.

Let the single digit be x, the ten digit is y, and the hundred digit is z

x+z=y7z-(x+y)=2

x+y+z=14

Use + to get: 8z=16, z=2

Use - to get: y=14-y,2y=14,y=7 and finally according to :x+7+2=14,x=5

This three-digit number is 275

Let the hundreds, tens, and units be x, y, and z respectively

x+z=y (1)

7x-(y+z)=2,7x-y-z=2 (2)x+y+z=14 (3)

8x=16x=2 2+z=y

2+y+z=14

2+2+z+z=14

z=5,y=7

So the number is 275

1、①*3-②：2x=3*48-128 x=8 y=12

2、①*9-②*7 32x=39*9-41*7 x=2 y=3

3、②*2-① 41（x-3）=27*2-13 x=4 y=1/3

4. According to the title: x0-y+1, substitute y=-1 x=2

Substituting the values of x and y yields: k=3

5. According to the title: x=y So: x=y=1 7. Substituting x=y=1 7 yields: a=11

Solution: The sailing speed and the current velocity of the ship in still water are x, and y is:

x+y)*x-y)*2=80

Solution: x=45, y=5

So the speed of the boat in still water and the speed of the current are 45 km h, 5 km h

The hydrostatic velocity of the ship is v1 and the current velocity is v2

80/80/2=v1-v2

v1 = 45 and v2 = 5

The speed of the boat in still water is x km h, and the current speed is y km h.

2(x-y)=80

Solution: x=45, y=5

Solution: Let the speed of the ship in still water be x kilometers per hour, and the current speed should be y kilometers per hour.

x+y）*x-y)*2=80

The solution is x=45 (km).

y = 5 (km).

Let the speed of the ship be x and the current velocity be y

x+y）*x-y）*2=80

The solution is x=45km h

y=5km/h

Let the sailing speed and current velocity in still water be v1 v2

v1 +v2）*

v1 -v2）*2=80

x+y=12①

x+y+z=10②

x-y-z=4③

2x=14x=7

Generation x = 7 in

7+y=12

y=5 generations, x=7;y=5 in

7-5-z=4

z=-2 means that the solution of the system of equations is x=7, y=5, z=-2

Subtract 1 from 2 to get z=-2, add 2 to 3 to get x=7, and substitute 1 to get y=5

Dear, is there anything else? It's a little hard, no!

①：x+z-3=0

2x-y+2z=2

x-y-z=-3

Solution: Eq=x+y=3 ; x=3-y

Substituting x=3-y into the equation yields: (3-y)-y-z=-3 ; So 6-2y=z

Substituting x=3-y with 6-2y=z yields: y=4 then x=2 ; z=1

Note that 4z=2*2z is known to be 2z=3x-5 substitution.

y+3x=6 substituting him into the equation gives 2x-3*(6-3x)-2(3x-5)=-3 to get x=7

Substituting x=7 into 3*7-2z=5 gives z= 8 and finally y=-15

Thank you, that's right.

y+2z=1 (1)

2x-3y-4z=-3 (2)

3x-2z=5 (3)

3) *2-(2)*3=9y+8z=19 (4)1) and (4) form a new system of binary linear equations and then solve them. y+2z=1 (1) 9y+8z=19 (4)

4)-(1)*4 gets: 5y=15, then y=3, substitute y=3 into (1) to get z=-1, substitute y=3, z=-1 into (2) to get x=1

x=y=z=