1 )
1st and 2nd equation (multiply 1st by -2 ):
-2x - 10 y + 8 z = 20
2 x - y + 5 z = -9
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- 11 y + 13 z = 11 / * ( -20 )
1st and 3rd:
- 2 x - 10 y + 8 z = 20
2 x - 10 y - 5 z = 0
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- 20 x + 3 z = 20 / * 11
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220 y - 260 z = -220
- 220 y + 33 z = 220
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z = 0, y = -1, x = - 5
2 )
2 x - y + 5 = -4
- 2 x + 3 y - 5 = - 10
Substitution: y = 2 x + 9
- 2 x + 3(2 x + 9 ) = -5
4 x = - 32, x = -8, y = -7, z = 5
3 )
x + y + z = 11
1.5 x+3 y +1.5 z = 21
x = 2 y
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3 y + z = 11 / * (-2)
6 y + 1.5 z = 21
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- 6 y - 2 z = -22
6 y + 1.5 z = 21
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-0.5 z = -1, z = 2, y = 3, z = 6
Answer: the store used 6 pounds of peanuts, 3 pounds of almonds and 2 pounds of raisins.
I'm pretty sure it's x/4=y
Answer:
The student's GPA is 2.8666.
Step-by-step explanation:
A grade is 4.0, B grade is 3.0, C grade is 2.0. For each credit, add the value of the letter grade. So:
Math, 2 credits, grade A: (4x2=8)
English, 5 credits, grade B: (5x3=15)
Physics, 4 credits, grade B: (4x3=12)
German, 4 credits, grade C: (4x2=8)
The numbers add up to 43, then divide by the number of credits (15) to get:
43/15=GPA of 2.8666.
Answer:
s=0.20p
Step-by-step explanation:
