1/2x - 1/2y = 2 - - - - - -Equation 1
4/3 x + 5y = - 1- - - - - -Equation 2
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Multiply equation 1 by - 8 and clear the fraction equation 2
1/2x - 1/2y = 2
-8(1/2x) - (-8)(1/2y) = - 8(2)
- 8/2x - (-8/2y) = - 16
- 4x + 4y = - 16. . . New equation 1
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4/3x + 5y = - 1
3(4/3x) + 3(5y) = 3(- 1)
4y + 15y = - 3 . . .New equation 2
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- 4x + 4Y = - 16
4x + 15y = - 3
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19y = - 19
19y/19 = - 19/19
y = - 1
The answer is y = - 1
Insert the y value into equation 2
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4/3x + 5y = - 1
4/3y + 5( - 1) = -1
4/3x + (- 5) = - 1
4/3x - 5 = - 1
4/3x - 5 + 5 = - 1 + 5
4/3x = 4
3(4/3x) = 3(4)
4x = 12
4x/4 = 12/4
x = 3
The answer is x = 3
Insert the x value into equation 2
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Check for equation 2
4/3x + 5y = - 1
4/3(3) + 5( - 1) = - 1
12/3 + (-5) = - 1
4 - 5 = - 1
- 1 = - 1
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Check for euation 1
1/2x - 1/2y = 2
1/2(3) - 1/2(- 1) = 2
3/2 - (-1/2) = 2
3/2 + 1/2 = 4
4/2 = 2
2 = 2
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The solution set { 3, - 1 }
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2006-11-09 00:27:52
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answer #1
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answered by SAMUEL D 7
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300x+200y=500 divide by potential of one hundred 3 x + 2 y = 5 (a million) and 7x-5y=31 ( 2 ) multiply ( a million ) by potential of five snd ( 2 ) by potential of two 15 x + 10 y = 25 and 14 x - 10 y = sixty two upload the two equation 29x = 87 divide by potential of 29 x = 3 replace in ( a million ) 9 + 2y = 5 2y = 5 - 9 2y = - 4 divde by potential of two y = - 2 the answer is : b) (x,y)=(3,-2)
2016-12-28 16:49:22
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answer #2
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answered by ? 3
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to find the intersecting points of the two equations, solve them simultaneously:
1/2x-1/2y=2 ------(1)
4/3x+5y=-1--------(2)
multiply eqaution (1) by 8:
4x -4y = 16----------(3)
multiply equation (2) by 3:
4x + 15y = -3------(4)
subtract eqaution (4) from (3) i.e. (3) -(4):
(4x-4y) - (4x+15y) = 16-(-3)
-19y = 19
y = -1
substitute y = -1 into equation (1):
1/2x - 1/2*(-1) = 2
1/2x + 1/2 = 2
1/2 x = 2-1/2 = 3/2
x = 3
therefore the point of intersection is given by the coordinates
(3, -1)
hope it helps!
2006-11-08 19:35:50
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answer #3
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answered by limck_dcp_cls 2
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(1/2x) - (1/2)y = 2
(4/3)x + 5y = -1
The quickest way looks to be substitution:
x/2 = 2 + y/2
x = 4 + y
4(4 + y)/3 + 5y = -1
16 + 4y +15y = -3
19y = -19
y = -1
x = 4 - 1
x = 3
x,y = (3,-1)
2006-11-08 20:03:21
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answer #4
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answered by Helmut 7
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subtract them
1/2x-1/2y=2
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4/3x+5y=-1
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2006-11-08 19:34:22
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answer #5
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answered by Anonymous
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