<span>25.7 years
The rule of 72 is a simple approximation on how long it will take to double your money. You simply divide 72 by the interest rate and you'll have your estimate on the number of years it will take. So
72 / 2.8 = 25.7 years.
To demonstrate that it's just an estimate, you can take the log of 2 and divide by the log of 1.028 to get the exact value. This far more complicated calculation gives the result of 25.1 years. And to be honest, the estimate of 25.7 years is more than close enough for such an quick and easy rule of thumb.</span>
Answer:
C and E
Step-by-step explanation:
To answer this question, we plug in the X values of the coordinates into the equation to see if they'll give us the corresponding Y value.
(X, Y)
Example:
Y = 5X
6 != 5 * 3
We do this for every coordinate point. If the problem doesn't make sense, it doesn't fall on the line. Let's test every one of these.
B. (0, 1)
1 != 5 * 0
C. (3, 15)
15 = 5 * 3
D. (4, 2)
2 != 5 * 4
E. (-1, -5)
-5 = 5 * -1
F. (-1, 5)
5 != 5 * -1
* For those who don't know, the != is how to say "not equal to" in computer science.
T too so yeah four of people
Answer:
r = √13
Step-by-step explanation:
Starting with x^2+y^2+6x-2y+3, group like terms, first x terms and then y terms: x^2 + 6x + y^2 -2y = 3. Please note that there has to be an " = " sign in this equation, and that I have taken the liberty of replacing " +3" with " = 3 ."
We need to "complete the square" of x^2 + 6x. I'll just jump in and do it: Take half of the coefficient of the x term and square it; add, and then subtract, this square from x^2 + 6x: x^2 + 6x + 3^2 - 3^2. Then do the same for y^2 - 2y: y^2 - 2y + 1^2 - 1^2.
Now re-write the perfect square x^2 + 6x + 9 by (x + 3)^2. Then we have x^2 + 6x + 9 - 9; also y^2 - 1y + 1 - 1. Making these replacements:
(x + 3)^2 - 9 + (y - 1)^2 -1 = 3. Move the constants -9 and -1 to the other side of the equation: (x + 3)^2 + (y - 1)^2 = 3 + 9 + 1 = 13
Then the original equation now looks like (x + 3)^2 + (y - 1)^2 = 13, and this 13 is the square of the radius, r: r^2 = 13, so that the radius is r = √13.
**4/5** is equal to .8, so 4/5 is the answer. to check, multiply .8 x 5 = 4
