SOLUTION: 3. Solve for X, Y, and Z in the following systems of three equations:
a. X + 2Y + Z = 6
X + Y = 4
3X + Y + Z = 8
b. 10X + Y + Z = 12
8X + 2Y +Z = 11
20
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Linear-equations
-> SOLUTION: 3. Solve for X, Y, and Z in the following systems of three equations:
a. X + 2Y + Z = 6
X + Y = 4
3X + Y + Z = 8
b. 10X + Y + Z = 12
8X + 2Y +Z = 11
20
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Question 174510: 3. Solve for X, Y, and Z in the following systems of three equations:
a. X + 2Y + Z = 6
X + Y = 4
3X + Y + Z = 8
b. 10X + Y + Z = 12
8X + 2Y +Z = 11
20X - 10Y - 2Z = 8
c. 22X + 5Y + 7Z = 12
10X + 3Y + 2Z = 5
9X + 2Y + 12Z = 14
You can put this solution on YOUR website! a.
X + 2Y + Z = 6
X + Y = 4 or x=4-y. Now replace x with (4-y) in the first & third equations & subtract them.
3X + Y + Z = 8
3(4-y)+y+z=8
-[(4-y)+2y+z=6] now subtract.
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12-3y+y-4+y-2y=8-6
-3y+8=2
-3y=2-8
-3y=-6
y=-6/-3
y=2 ans.
x+2=4
x=4-2
x=2 ans.
3*2+2+z=8
6+2+z=8
z=8-8
z=0 ans.
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b. 10X + Y + Z = 12
8X + 2Y +Z = 11
20X - 10Y - 2Z = 8 add all 3 equations.
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38X-7Y=31
NOW SUBTRACT EQUATION 2 FROM EQUATION 1.
10X+Y+Z=12
-(8X+2Y+Z=11)
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2X-Y=1 NOW MULTIPLY THIS EQUATION BY -7 & ADD THEM.
-14X+7Y=-7
38X-7Y=31
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24X=24
X=24/24
X=1 ans.
2*1-Y=1
2-Y=1
-Y=1-2
-Y=-1
Y=1 ans.
10*1+1+Z=12
10+1+Z=12
11+Z=12
Z=12-11
Z=1 ans.
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c. 22X + 5Y + 7Z = 12
10X + 3Y + 2Z = 5
9X + 2Y + 12Z = 14
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