Answer: So when you double the radius, the area goes up by 4 times because 2 squared is 4. The area will always go up by the square of how much the radius goes up. By contrast, the circumference will only double -- from 12.56 to 25.12 because you do not square the radius (or diameter) -- you just multiply it by pi.
Answer:

Step-by-step explanation:
Given


Required
The explicit formula
First, calculate 
Set n=2; So:


Substitute -25 for 


Calculate the common difference (d)



So, the nth term is:


Open bracket

Collect like terms


Answer:
She should have substituted y = 17 - 2x in the first equation
Step-by-step explanation:
3x + 4y = 33
2x + y = 17
y = 17 - 2x
3x + 4(17 - 2x) = 33
3x + 68 - 8x = 33
5x = 35
x = 7
y = 17 - 2(7)
y = 3
x = 7, y = 3
Only one solution
Answer:
Equation 1
In the story it said Eli's mom doubled the money he left, that is what the two represents. 10 is the original amount he had. -k is the money he lost.
Equation 2
20 is the the result of the original 10 being multiplied. -2k, now the 2 is still the amount that the mom doubled his amount by, and the k is how much money Eli lost.
Hope this helps!!
Answer:
$390 you divide 520 by 4 so 520/4=130 now we subtract 130 from 520, 520-130=390
Step-by-step explanation: