Answer:
x = 5
Step-by-step explanation:
4x + 2y + z = 24
2x - 3y - z = 2
5x + y + 2z = 21
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Eliminate z
Add the 1st and 2nd eqn
4x + 2y + z = 24
2x - 3y - z = 2
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6x - 1y = 26 eqn A
Multiply the 2nd eqn by 2, then add the 3rd.
4x - 6y -2z = 4
5x + y + 2z = 21
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9x - 5y = 25 eqn B
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Now you have 2 eqns in 2 unknowns, not 3.
Multiply eqn A by 5 and subtract eqn B.
30x - 5y = 130 eqn A times 5
9x - 5y = 25 eqn B
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21x = 105
x = 5
Replace x with -2 and solve:
A) -2 + -2 = -4 which is not less than or equal to -8
B) 2 + -2 = 0, this is greater than or equal to -8
C) -2 + -2 = -4, this is not less than -8
D) 2 + -2 = 0, this is not greater than 8
Answer: B is true
Answer:
The square root of this is 80047
Step-by-step explanation:
Answer:
Step-by-step explanation:
a)
the sum of all angles in a quadrilateral must be 360º
y+88+25+35 = 360
y = 360=88-25-35
y = 212º
b)
the sum of all angles in an octagon must be 1080º
45+45+140+140+6y = 1080
6y = 1080-90-280
6y = 710
y = 710/6
y=~ 118,3º
