Q1. The answer is x = 1, y = 1, z = 0
<span>(i) -2x+2y+3z=0
</span><span>(ii) -2x-y+z=-3
</span>(iii) <span>2x+3y+3z=5
</span><span>_________
Sum up the first and the third equation:
</span>(i) -2x+2y+3z=0
(iii) 2x+3y+3z=5
_________
5y + 6z = 5
Sum up the second and the third equation:
(ii) -2x-y+z=-3
(iii) 2x+3y+3z=5
_________
2y + 4z = 2
(iv) 5y + 6z = 5
(v) 2y + 4z = 2
________
Divide the fifth equation by 2
(iv) 5y + 6z = 5
(v) y + 2z = 1
________
Multiple the second equation by -3 and sum the equation
(iv) 5y + 6z = 5
(v) -3y - 6z = -3
________
2y = 2
y = 2/2 = 1
y + 2z = 1
1 + 2z = 1
2z = 1 - 1
2z = 0
z = 0
-2x-y+z=-3
-2x - 1 + 0 = -3
-2x = -3 + 1
-2x = -2
x = -2/-2 = 1
Q2. The answer is x = -37, y = -84, z = -35
<span>(i) x-y-z=-8
(ii) -4x+4y+5z=7
(iii) 2x+2z=4
______
</span>Divide the third equation by 2 and rewrite z in the term of x:
(iii) x+z=2
z = 2 - x
______
Substitute z from the third equation and express y in the term of x:
<span>x-y-(2-x)=-8
x - y - 2 + x = 8
2x - y = 10
y = 2x - 10
______
Substitute z from the third equation and y from the first equation into the second equation:
</span><span>-4x + 4y + 5z = 7
-4x + 4(2x - 10) + 5(2 - x) = 7
-4x + 8x - 40 + 10 - 5x = 7
-x -30 = 7
-x = 30 + 7
x = -37
y = 2x - 10 = 2*(-37) - 10 = -74 - 10 = -84
z = 2 - x = 2 - 37 = -35</span>
C 87 the median :::::::::::::
Based on the given nomenclature of angles, I think the illustration would look like that shown in the attached picture. The common vertex is point B, that's why the middle point of the given angles is B. Now, according to Angle Addition Postulate, the individual interior angles should sum up to the total angle. So, the equation would be
m∠ABD = m∠ABC + m∠CBD
m∠ABC = m∠ABD - m∠CBD
m∠ABC = 85° - m∠CBD
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Answer:
15..
Step-by-step explanation:
4, 10, 14, 18, 22, 22
Mean = (4 + 10 + 14 + 18 + 22 + 22)/6
= 90/6
= 15.
Number to be added, 'y'
For the mean to be the same
(90 + y) / 7 = 15
90 + y = 15 × 7
90 + y = 105
y = 105 - 90
= 15
Answer: the answer is 45.5, which the second bubble down.
Step-by-step explanation: