Answer:
z = -12
Step-by-step explanation:
The given system of equations is:
xy/(x + y) = 1 ...........................(1)
xz/(x + z) = 2...........................(2)
yz/(y + z) = 3...........................(3)
From (1): x + y = xy
=> y = xy - x
y = x(y - 1)
x = y/(y - 1).......................................(4)
From (2): 2(x + z) = xz
=> 2x + 2z = xz
2x = xz - 2z
2x = z(x - 2)
z = 2x/(x - 2) ....................................(5)
From (3): 3(y + z) = yz
=> 3y + 3z = yz
3y = yz - 3z
3y = z(y - 3)
z = 3y/(y - 3)....................................(6)
Comparing (5) and (6)
2x/(x - 2) = 3y/(y - 3)
2x(y - 3) = 3y(x - 2)
2xy - 6x = 3xy - 6y
6(y - x) = xy .................................(7)
But from (1): xy = x + y
Using this in (7), we have
6(y - x) = x + y
6y - y - 6x - x = 0
5y - 7x = 0
5y = 7x
x = 5y/7................................................(8)
Using this in (4)
5y/7 = y/(y - 1)
1/(y - 1) = 5/7
(y - 1) = 7/5
y = 1 + 7/5
y = 12/5..........................................(9)
Using this in (8)
x = 5(12/5)/7 = 12/7 .......................(10)
Using (10) in (5)
z = 2x/(x - 2)
z = 2(12/7) ÷ (12/7 - 2)
= 24/7 ÷ -2/7
= 24/7 × (-7/2)
= -24/2 = -12
z = -12.
Answer:
2370 cm²
Step-by-step explanation:
2(32·15+15·15+15·32) = 2370
Answer:
$52.44
Step-by-step explanation:
So here is the explanation. $240•.80= 192 (80% as a decimal is .80) 240-192=48. 48•.0925=4.44 which you add 48, and get a sum of $52.44
Hope this helps :)
The striped wall and the floor intersect at a 90 degrees angle since they are perpendicular.
<h3>What is an
angle?</h3>
An angle is formed when two or more lines intersect at a point. Types of angles are<em> acute, obtuse, and right angled</em>.
Two lines are said to be perpendicular if there is a 90 degrees angle between them.
The striped wall and the floor intersect at a 90 degrees angle since they are perpendicular.
Find out more on angle at: brainly.com/question/25716982
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So you gotta change the second one to slope int form and it will become -3y=18x-54 which means that it's A because parallel lines can't be parallel if the slopes are different. (pretty sure this is right but who knows)