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.
Step-by-step explanation:
given,
point = ( -10, -8 ) and ( -8, -16 )
we know,
slope = y2 - y1 / x2 - x1
x1 , y1 = (-10 , -8 )
x2 , y2 = ( -8, -16 )
after inserting the values we got,
→ -16 - (-8 ) / -8 - (-10)
→ -8/2 → -4
therefore, slope of line is -4.
hope this answer helps you dear...take care and may this answer helps you dear!.
Answer:
189
Step-by-step explanation:
45% x2= 90%
10% of 90= 9
90+90=180
plus that 10%
180 + 9 = 189
sorry if I'm wrong I'm trying
Answer: D. Predictive validity
Step-by-step explanation: Predictive validity can be explained as a method of determining the degree or level of correctness of a prediction using pre-existing information or data and values obtained from the actual measurement.
In the scenario above, the researchers investigates the correlation or relationship between the predicted value obtained using a pre- admission HESI examination, high school GPA, and SAT scores and the actual grade received upon completion of the first year. This process is to analyze or determine the validity of our prediction.
Answer:
16 people
Step-by-step explanation:
22+22=44 8+8=16
