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5/x+6/y=8(1)
1/x-3/y=-11(2)
1), (2) multiply the two formulas by xy.
5y+6x=8xy(3)
y-3x=-11xy(4)
4) Multiply by 2 to get 2y-6x=-22xy(5).
5) + (3) gives 7y = -14xy
So x= 1 2(6).
Bring (6) into (4).
y=1/3
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Summary. Solve the system of equations x: y = 5:6, (x 2): y = 7: 9x 5y 6 substituting 5y 6-2 7y 915y 18-14y 18 2y 36x 5 6 36 30
Solve the system of equations x:y=5:6,(x2):
y=7:9 to solve the equation without jujube base group x:y=5:
6, (x 2): y=7: 9x 5y 6 substitution 5y 6-2 7y 915y 18-14y 18 2y 36x 5 6 36 30 Kujin Iwano
The first time a rope is used 1 4, the second time it is used 15 meters, and the ratio of the number of meters used to the remaining meters is 2:3 How many meters the rope is originally long.
Let the original length be x meters (x 4+15) :(x-x 4-15) 2: 33x 4+45 3x 2-30
15=3x/4
75=3x/4
The length of the rope is 100 meters.
15 and 75 are always equal to 3x 4
Sorry, the one above was written incorrectly.
The bottom was changed immediately.
75=3x/4
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2(x-y)/3
x+y/4=-1
1)6(x+y)-4(2x-y)=16
2) Solution: 1) Multiply both sides of the equation by 12.
8(x-y)-3(x+y)=-12
Mergers of the same kind.
5x-11y+12=0
3) (2) Consolidation of similar items.
10y-2x-16=0
4) (3) * 2 + (4) * 5.
28y-56=0
So y=2 substituting y=2 into (1) gives x=2
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x+y=-1 1)
x2+4y2=8 2)
1) Quarrel with the spine stupidity, get y=-1-x
Substitution 2), get.
x^2+4(-1-x)^2=8
5x^2+8x-4=0
5x-2)(x+2)=0
x1=2/5,x2=-2
y1=-7/5,y2=1
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x -y =5(x+y) (1) x +xy+y =43 (2) solution: obtained from (1).
x+y)(x-y-5)=0
x=-y x=y-5
Substituting x=-y into (2) to get it.
y²=43y=√43 y=-√43
x=- 43 x= 43y= 43 y=- 43 substitute x=y-5 into (2).
y-5)²+y(y-5)+y²=43
3y²-15y-18=0
y²-5y-6=0
y-6)(y+1)=0
y=6 y=-1
x=1 x=-6
y=6 y=-1
x=-√43 x=√43 x=1 x=-6
y=√43 y=-√43 y=6 y=-1
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x^2-5x=y^2+5y
x-5/2)^2=(y+5/2)^2
x-5 2=y+5 2 or x-5 2=-y-5 2
x=y+5 or x=-y
y 2+10y+25+y 2+5y+y 2-43=0 or y 2-y 2+y 2=43
3y^2+15y-18=0
y^2+5y-6=0
y=1 or y=-6 or y=root43 or - root43
x=6 or x=-1 x=-root number 43 or root number 43
So x=6 x=-1 x=-root43 x=root43
y=1 y=-6 y=root43 y=- root43
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x -y =5(x+y) (x-y)(x+y)-5(x+y)=0 (x+y)(x-y-5)=0 x=-y or x=y+5
x²+xy+y²=43
x+y)²-xy=43
Substituting x=-y into it, we get:
0+y²=43 y=±√43
x = 43 or x = 5 43
Substituting x=y+5 yields:
2y+5)²-y²-5y=43
3y²+15y-18=0
y²+5y-6=0
y+6)(y-1)=0
y=-6 or y=1
x=6 or x=-1
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(x+y)(x-y)=5(x+y)
x-y=5 into the second equation.
Got it.
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5/9*x+4/9*y=50
3/5*x+2/5*y=
1) Multiply both sides of the equation by 9, 5x+4y=450
2) Multiply both sides of the equation by 5, 3x+2y=243
3)-(4)×2,-x=-36
x=36 substituting x=36 into (3) to get y=
The solution of the system of equations is x=36,y=
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The question should be: 6x x -1 +5x x-1 = x+4 x+1 ?
4x²+8x+4=0
x1=x2=﹣1
When x = 1, x+1 x-1 = 0
x1=x2=1 is the added root of the original fractional equation, and the original equation has no solution.
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