Tn=n²+3
from 4 to 7....the difference is 3, then from 7 to 12 the difference is 5 and from 12 to 19 the difference is 7
therefore we constantly add 2 to the difference
The answer to the problem is 6,-6
Summaation of a sequence
or see a smaller scale
from 1 to 10
notice
1+10=11
2+9=11
etc
5+6=11
10/2=5
there are 5 pairs
5*11=55
so
1 to 100
1+100=101
2+99=101
...
50+51=101
100/2=50
there ar 50 pairs
50 times 101=5050
the sum is 5050
<h2>Greetings!</h2>
Answer:
≅ 586.8
Step-by-step explanation:
Take x to be the width, if the length is 5x bigger than the width, then this can be shown by 5x.
The total perimeter is:
(2 * x) + (2 * 5x) because each side has another parallel one.
This means that 2x + 10x = 130
12x = 130
Divide both sides by 12:

x = 
So the area = length * width
x * 5x = area
Substitute the values in:
= 586.8055... ≅ 586.8
So the approximate area is 586.8
<h2>Hope this helps!</h2>