Answer:
Step-by-step explanation:
4.5 miles
I don't think it's proportional, because in order for a question to be a proportional question has/could be to be like this:
Gasoline costs $2.79 per 2 gallon. How much will it cost for 8 gallon. Then, we cross multiply and all to find the answer.
The answer is 6*4*4 square inches where 4*4 gives us the area of one square and multiplying by 6 gives you the total surface area.
Answer:
Nolan hitted 8 home runs
Step-by-step explanation:
Let's call the number of home runs that Nolan hitted by N, and that Davis hitted by D.
So, we can write the following equations:
N = 2 * (D - 6)
N + D = 18
Now we can solve the system of equations, using the value of N from the first equation in the second one:
2 * (D - 6) + D = 18
2*D - 12 + D = 18
3*D = 30
D = 10
Now we find N:
N + D = 18
N + 10 = 18
N = 8
So we have that Nolan hitted 8 home runs.
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.
