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:
.00019
Step-by-step explanation:
.00019
first 0: tenths
2nd 0: hundredths
3rd 0: thousandths
4th 1: ten thousandths
5th 9: hundred thousandths
The anwser is c your welcome
Option B is the correct answer because you start with 15 gallons (y-intercept), and the car consumes or decreases at 0.03 gal/per mile (your slope or m).
Fraid not. This time, you did it left.
The tool to use is "Vertical" angles are equal. (They don't add up to 180 degrees.)
3y + 120 = 5y + 100
(you should fill in the missing steps)
y = 10°
The upper/lower pair of vertical angles are both 150°.
.
2x = 6x - 60
(you should fill in the missing steps)
x = 15°
The left/right pair of vertical angles are both 30°.
It's any two angles NEXT TO each other that add up to 180°.
Notice here that (150° + 30°) = 180° .
