9514 1404 393
Answer:
21x² +20x +100 = 0
Step-by-step explanation:
We know the sum of the roots of x² +bx +c = 0 is -b, and their product is c. If the roots are α and β, then ...
The sum of the roots of the new equation will be ...
-b' = (α+1/β)+(β+1/α) = (α+β) +(1/α +1/β) = (α+β)(1 +1/(αβ))
The product of the roots of the new equation will be ...
c' = (α+1/β)(β+1/α) = αβ +2 +1/(αβ)
Using the above relations for (α+β) and αβ, we find that ...
-b' = (-b)(1 +1/c)
c' = c + 2 + 1/c
For the given equation, our definition of b and c is ...
b = 2/3
c = 7/3
so the new equation has values ...
b' = (2/3)(1 + 1/(7/3) = (2/3)(10/7) = 20/21
c' = 7/3 + 2 + 1/(7/3) = 13/3 + 3/7 = 100/21
So, the equation with the roots of interest is ...
x² +20/21x +100/21 = 0
Multiplying by 21 gives ...
21x² +20x +100 = 0
2000 dollars is owed with 9% interest rate.
Now, assuming that for 10 years, it is not being paid.
Let's calculate for the money that is now owed.
=> 2000 dollars * . 09 = 180 dollars for 1 years
=> 180 dollars * 10 years = 1800 dollars
=> 2000 + 1800 = 3800 dollars for 10 years.
Answer:
8
Step-by-step explanation:
The easiest way to find out is with a calculator.
0.125 = 1/8=1÷8
Average rate of change means find the slope of the secant line. So if there is a function f(x) and you want to find the average R.O.C over the interval [a,b], it would be (f(b)-f(a))/(b-a)
1. (f(3)-f(1))/(3-1)= (0-(-2))/2= 1, so D.
2. Same concept; (8-4)/(3-1)=2, so A.
3. Again, (39-(-1))/5= 8, B.