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.
For simple interest, the formula is I = PRT, where I = interest, P = principal borrowed or deposited, R = rate as a decimal, and T = time in years.
Your information:
I = (870)(0.08)(5)
I = 348
Add the interest to the principal for your total balance
348 + 870 = $1218 will be the total balance in the account.
Answer:
x=-3, x=1, x=8
Step-by-step explanation:
When you have to find the zero of an equation like (x+3) all you have to do is solve for x.
x+3=0 equal the equation to zero
x+3-3=0-3 cancel out 3
x=-3 answer
If you have to find the zero of an equation like f(x)=-2x^2 - 5x + 7 then you would have to factor the equation.
7*-2=-14 multiply
-7 & 2 find the two numbers that when multiplied =14 and when added = -5
(2x^2 + 2) (-7x + 7) replace -5 with -7 & 2
-2x (x - 1) -7 (x - 1) factor
(x - 1) (-2x - 7) rewrite
1st: x - 1 = 0
x = 1 : Answer
2nd: -2x - 7= 0
-2x - 7 + 7 = 0 + 7
-2x = 7
-2x / -2 = 7 / -2
x = 7 / -2 : Answer
Answer:
tan -1 (8/10)
Step-by-step explanation:
hope it helps :3
Answer:
The length of BC is 17 units
Step-by-step explanation:
we know that
An isosceles triangle has two equal sides and two equal angles
In this problem we have an isosceles triangle
Because
m∠ACB=m∠ABC ----> given problem
so
AC=AB
substitute the given values
solve for x
therefore
The length of BC is 17 units
