Answer:
c
Step-by-step explanation:
use foil so u multiply x and then x and 7 then -3 and x and 7 finally simplify
Answer: x + y + z = 4
-1 + 2 + 3 = 4
Explanation:
2x + 3y - z = 5 (1)
x - 3y + 2z= -6 (2)
3x + y - 4z = -8 (3)
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2x + 3y - z = 5 (Add (1) and (2)
X - 3y + 2z = -6
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3x + z = -1 (4)
3x + y - 4z = -8 Add (3) and (2)
x - 3y + 2z = -6
————————
3(3x + y - 4z = -8)
x - 3y + 2z = -6
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9x + 3y - 12z = -24
x -3y + 2z = -6
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10x - 10z = -30
x - z = -3 (5)
Add (4) and (5)
3x - z = -1
x - z = -3
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4x = -4
x = -1
Plug x = -1 in (5)
x - z = -3
-1 - z = -3
-z = -2
z = 2
Plug x and z in (2):
x - 3y + 2z = -6
-1 - 3y + 2(2) = -6
-1 - 3y + 4 = -6
-3y + 3 = -6
-3y = -9
y = -9/-3
y = 3
Therefore, y + z + x = 3 + 2 -1 = 4
I think it's 16. 8 different numbers have dots (which represent gauges) above them. if you count them they total up to 16.
