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:
3 roots
Step-by-step explanation:
(9x+7)(4x+1)(3x+4)=0
x=-7/9 or - 1/4 or - 4/3
The expression for the total cost of their trip is 7 + 2x + 3y.
As per the question, assuming the number of bottles to be x and number of bags to be y. The equation will have one time fee of admission, product of cost of bottles and number of bottles and product of cost of bags and number of chips bags.
The one time fee and two products will be added to form the expression. Forming the equation now -
Expression = 7 + 2x + 3y
Therefore, the expression of trip when x bottles of water were bought during the visit is 7 + 2x + 3y.
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Answer:
x = 3
Step-by-step explanation:

Square both sides of the equation


(x - 3)(x - 5) = 0
x = 3 or 5
Now, you must always check your results because a result may not satisfy the original equation.
If x = 3, then
and 3 - x = 3 - 3 = 0
So 3 satisfies the original.
If x = 5, then
, but 3 - x = 3 - 5 = -2. Therefore, 5 does NOT satisfy the original equation.
That means that x = 3 is the solution to the equation.
Answer:
1.2
Step-by-step explanation:
You simply have to look for a point on the graph that has an x-coordinate of -6. Only one is (-6. 1.2), so 1.2 is your answer.