648.566 Km is the answer. :)
The y-intercept is (0, -8)
if you set the equation to slope intercept format you get
y=-2x-8
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
------------------------------
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
------------------------
3 y + z = 11 / * (-2)
6 y + 1.5 z = 21
------------------------
- 6 y - 2 z = -22
6 y + 1.5 z = 21
------------------------
-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.
<span>Simplifying
4x = 92
Solving
4x = 92
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Divide each side by '4'.
x = 23
Simplifying
x = 23</span>