Answer:
-2n²
Step-by-step explanation:
Using the image attached:
We see that the second differences (blue ones) are all equal so we conclude that this is a quadratic sequence.
The quadratic sequence has the form:
To find the value of a we just divide second difference ( -4 ) by 2:
Now we have:
Substitute 
and 
into the equation above:
Since 
= -2 and 
= -8 , after simplification we have:
The solution of this system is:
The general term is :
Answer: 
Explanation:
Multiplying by 1/2 is the same as dividing by 2.
For example, if you have 10 slices of cake and 2 friends, then each friend gets 10/2 = 5 slices. We could also say 
The fraction 1/2 converts to the decimal form 0.5, which means 
Answer:
(4,2)
Step-by-step explanation:
(4)-4(2)=-4
5(4)-4(2)=12
Subtract 1 from both sides
3 - 1 = -2x
Simplify 3 -1 to 2
2 = -2x
Divide both sides by -2
-1 = x
Switch sides
<u>x = -1</u>
Leah, she ran farther by 1/21
How you get the answer:
5/7
Multiply 7x3 to get the denominator and do the same to the numerator 5x3! Which is 15/21
To get 21 from 2/3 is to multiply 3x7 (denominator) and 2x7 (numerator) to get 14/21
15/21 > 14/21 so Leah ran farther by 1/21
