【1】5x-3y=12 【2】9x-5y+z=-6 3x+4y=-8 9x+y+4z=3 -9x+3y-5z=0

【1】5x-3y=12 【2】9x-5y+z=-6 3x+4y=-8 9x+y+4z=3 -9x+3y-5z=0

(1) (2) 9x-5y + Z = - 6 (1) {9x + y + 4Z = 3 (2) - 9x + 3y-5z = 0 (3)) (2) 6y + 3Z (2) - 6y + 3Z (3)) (3) 6y + 3Z (3) 6y + 3Z (3) 6y + 3Z (3) 6y + 3Z (3) 6y + 3Z (3) 6y + 3Z (3) 6y + 3Z (3) 6y + 3Z (3) 6y + 3Z (3) 6y + 3Z (3) 6y + 3Z (3) 6y + 3Z (3) 6y + 3Z (3) 6y + 3Z (3) 6y + 3Z (3)

Let the solution of the system of equations x + y = 2,5x + 3Y = 2A satisfy x > 0, Y > 0, and find the integer a

x+y=2,
5x+3y=2a
The first formula is multiplied by five
5x+5y=10
Subtract the second formula to get
2y=10-2a
y=5-a
Take in the first formula
x=a-3
The solution satisfies x > 0, Y > 0
So 5-a > 0 A0 a > 3
3

It is known that the solution of the system of equations x + 3Y = 5,4x-3y = a + 4 satisfies the equation 5x + 2A = 3, then the value of a is ()

Formula x + 3Y = 5 -- 1
4x-3y = a + 4 -- 2
Formula 5x + 2A = 3 -- 3
Formula 1 + formula 2 leads to formula 5x-a = 9 -- 4
3A = - 6 for Formula 3 - 4
So a = - 2

3X-4Y-5Z=18 2X+y-6z=8 X+3Y+Z=22

3x-4y-5z = 18 (1) 2x + y-6z = 8 (2) x + 3Y + Z = 22 (3) z = 22-x-3y (4) is substituted by (2) 2x + y-132 + 6x + 18y = 22, that is, 8x + 19y = 140 (5) is substituted by (1) 3x-4y-110 + 5x + 15y = 18, that is, 8x + 11y = 128 (6) and (5) is substituted by (6) 8y = 12Y = 1.5 (6) is substituted by (6) 12 + 11y = 12811y = 116y = 116 / 11 (4)

Known: 2x + 3Y = 18, 3x + 4Y = 25, how many are x and y

2x+3y=18 （1）
3x+4y=25 （2）
(1) X 3
6x+9y=54 （3）
(2) X 2
6x+8y=50 （4）
(3) - (4), got it
y=4
Substituting y = 4 into (1), we get
2x+12=18
2x=6
x=3
So x = 3, y = 4

If x * x-2xy-3y * y = 0 and X is not equal to 0 and Y is not equal to 0, then 5x-4y / 5x + 4Y=

x²-2xy-3y²=0
x²-2xy+y²-4y²=0
（x-y）²-4y²=0
(X-Y) ² = 4Y & #178; then
① X-Y = 4Y means x = 5Y. ② X-Y = - 4Y means x = - 3Y. ③ Y-X = 4Y means x = - 3Y is the same as ②. ④ Y-X = - 4Y means x = 5Y is the same as ①
From (1)
5x-4y/5x+4y=（25y-4y）/（25y+4y）=21y/29y=21/29
From (2)
5x-4y/5x+4y=（-15y-4y）/（-15y+4y）=-19y/-11y=19/11

(X-Y) (x-4y) = 0, what are x and y equal to?

Classmate, this problem can't work out how much X and y are equal to, only how much X: y = can be worked out
Specific methods:
∵ （x-y)(x-4y)=0,
Ψ X-Y = 0 or x-4y = 0
Ψ X: y = 1:1 or X: y = 4:1
If you agree with my answer, please click the "select as satisfied" button below,

If XY is opposite to each other, what are the values of 3x-10 + 3Y and Y / 5x (y is not equal to 0)

3x-10+3y
=10+3(x+y)
=10+0
=10
y/5x
=-x/5x
=-1/5

Given that 5x-2y = 0 and XY is not equal to 0, then 10x-3y is divided by 10x + 5Y

The solution of 5x-2y = 0 is y = 5x / 2
10X-3Y=10X-3(5x/2)
=(1/2)(20X-15X)=5X/2.
10X+5Y=10X+5(5x/2)
=(1/2)(20X+25X)
=45X/2.
10X-3Y/10X+5Y
=(5X/2)/(45X/2)
=1/9.

Solve the equations 1.3 (x + y) - 4 (X-Y) = 4, x + Y / 2 + X-Y / 6 = 12.5x + 4Y + Z = 0, 3x + y-4z = 11, x + y + Z = - 2

1.3 (x + y) - 4 (X-Y) = 4, (1) x + Y / 2 + X-Y / 6 = 1 (2) from (1), x = 7y-4, substituting (2), 14y-y / 3 = 9, y = 27 / 41, x = 25 / 412.5x + 4Y + Z = 0, (1) 3x + y-4z = 11, (2) x + y + Z = - 2 (3) 4 (1) + (2): 23x + 17Y = 11 (4) (1) - (3): 4x + 3Y = 2 (5) 3 (4) - 17 (5): x = - 1 from (5), y = 2