The pyhtagorean states that to find c, use the eqaution,

.
Substitute 1 for a and 20 for b;
c^2=1+400
c^2=401
c=
which is about 20.02
Hope this helps.
Answer:
23/25
Step-by-step explanation:
hope this helped.
Answer:
s=64
Step-by-step explanation:
Answer:
-125
Step-by-step explanation:
Each term is 7 less than the previous term.
1st term: 15
2nd term: 15 - 7
3rd term: 15 - 7 - 7 = 15 - 2(7)
4th term = 15 - 7 - 7 - 7 = 15 - 3(7)
Notice that each term is 15 minus a multiple of 7. The multiple is obtained by multiplying 7 by 1 less than the term number.
The formula is:

For the 21st term, multiply 7 by 20, and subtract from 15.
7 × 20 = 140
15 - 140 = -125
Using the formula:

Answer: -125