-
The fourth one is very simple! Add the three equations and divide them by 2 to get: x+y+z=45
Then subtract the first, second, and third equations from the equation obtained above, respectively, to get:
z=18;x=12;y=15。
-
1)z=x+y
2x-3y+2z=5
x+2y-z=3
Solution: Substituting z=x+y into the remaining two formulas, then.
2x-3y+2(x+y)=5
x+2y-x-y=3
To simplify: 4x-y=5
y=3 substituting y=3 into 4x-y=5 yields: x=2 substituting x=2 and y=3 into z=x+y
z=52) x+2y+3z=11 a
x-y+4z=10 b
x+3y+2z=2 c
Solution: a-b 3y-z=1 d
c-a y-z=-9 e
d-e 2y=10 gives y=5
Substituting y=5 into 3y-z=1 gives z=14
Substituting y=5,z=14 into x+2y+3z=11 gives x=-413)x:y=1:5 3
y:z=5:6
x+y+2z=40
Solution: (5 3) x=y
z=(6/5)y
then z=(6 5)*(5 3)x z=2xx+(5 3)x+2x=40
x=60 7 y=100 7 z=120 7
-
1.Substituting one formula into three: y=3 and substituting one formula into two: x=2 solution: z=5
-
If you want to solve a ternary equation, you must have three different equations to solve it. Then use some two equations, eliminate one of them, become a binary system of equations, and then solve it. For example:
The sum of the three numbers of A and B is 26, A is 1 greater than B, and the sum of A and C is 18 greater than B.
Solution: Let A be x, B be y, and C be z.
Then: x+y+z=26
x-y=12x+z-y=18③
Transform the equation to x=1+y
Then replace the x in and with 1+y.
So. It becomes 1+y+y+z=26
That's 2y+z=25
This becomes 2(1+y)+z-y=18
That's z+y=16
Finally use the transformed - and it's done.
y=9 and then y=9
Substituting the transformed , so x=10
Finally, y=9, x=10 are substituted into the original ones.
That's 9 + 10 + z = 26
z=7, so x=10
y=9z=7
-
y=ax²+bx+c
When x=1 and y=3, the equation can be written as a+b+c=3 and denoted as an equation.
When x=2 and y=-1, the formula can be written as 4a+2b+c=-1 and denoted as the Zhongshan equation.
When x=3 and y=15, the equation can be written as 9a+3b+c=15 as an equation.
Equation 2-1 yields 3a+b=-4
Write as Equation 4
Equation 3-2 yields 5a+b=16
Write as Equation 5
Equation 5-4 yields 2a=20
then we get a=10
Bringing in Equation 4 gives us b = -34
Sell a and b respectively to the c=27 of equation 1
This yields a=10
b=-34c
The equation is y=10x-34x+27 from. x=5. y=107
-
1)x+2y+2z=3
3x+y-2z=7
2x+3y-2z=10. 4x+3y=10
3x+5y=13
3- *4, got.
y=2x=1
Substituting x=1y=2 into , gets.
z=-12)x-y=-1
2x+y+3z=5
x+y-z=1
*3, got. 5x+4y=8
4+, got.
x=4/9y=13/9
Will. x=4/9
y=13/9
Substitution, got.
z=8/93)x+y=8
y+z=-1
x+z=5-, get.
y-x=-6. y=1x=7 will.
y=1 substitution
Get. z=-2
4)x-y=2
z-x=3y+z=-1. y-x=4, the disadvantages are gained.
y=-3x=5
Will. x = 5 substitution. z=2
5)x-y-z=2
3x+5y+7z
4x-y+2z=26
5+, got.
4x+z=17
x+z=8-, get.
x=3z=5 will. x=3
z = 5 substitution into the shirt, nuclear divination cavity.
y=-4
-
(1)-(2) De:
x-y=5(4)
2) 3-(3) De:
5x+7y=76;(5)
5) (4) 7 get:
12x=111;
x=111/12=37/4;
Bring in (4) to:
y=17/4;
Bring in (1) to:
z=11/4;
So, the solution of the original system of equations is {x=37 4,y=17 4,z=11 4.}
-
- Find b
And then there are only two variables.
-
{x-2y=-9
1{y-z=3
2{2z+x
3 solution: obtained by formula 1.
x=-9+2y
Substitute x=---9+2y into formula 3 to get.
2z-9+2y=47
42 and 4 form a system of equations.
y-z=32z-9+2y=47
x=9+2y
z=y-32z+x=47 >>>More
3a-b 3=2a+c 5 ==> a=b 3+c 52a+c 5=2b+c 7 Substituting the above formula a. >>>More
Solution: Consists of 1200+4y=500x
2400+20x=20y. >>>More
If the large bottle is x bottle, then the small bottle is y bottle, then there are: 500 * x + 250 * y = (one ton = 1000kg = 1000000g). >>>More
Assuming that the speed of the airplane is xkm h, the flight distance from airport A to airport B is ykm, and according to the "how long does it take for an airplane to fly from airport A to airport B" downwind, you can list Equation 1: >>>More