Answer:
A) 8, 15, 17.
Step-by-step explanation:
Right triangle obey the Pythagorean theorem. Thus, we choose the two smaller numbers (being the cathetus) and if after applying the P. Theorem we get the biggest of each option (the hypotenuse) that means that those numbers could be the sides of a right triangle.
The Pythagorean theorem states that: 
Thus:
Option A:
→ 17 = 17 OK!
Option B:
→ 10 ≠ 12 NO
Option C:
![\sqrt{9^2+11^2} = [tex]\sqrt{202}](https://tex.z-dn.net/?f=%5Csqrt%7B9%5E2%2B11%5E2%7D%20%3D%20%5Btex%5D%5Csqrt%7B202%7D)
[/tex] → 
≠ 21 NO
Option D:
→ 
≠ 16 NO
15 is A, 22+X=8
I don't have time to solve the rest RN but will come back later
Answer:
Tn = 64-4n
Step-by-step explanation:
The nth term of an AP is expressed as:
Tn = a+(n-1)d
a is the common difference
n is the number of terms
d is the common difference
Given the 6th term a6 = 40
T6 = a+(6-1)d
T6 = a+5d
40 = a+5d ... (1)
Given the 20th term a20 = -16
T20 = a+(20-1)d
T20 = a+19d
-16 = a+19d... (2)
Solving both equation simultaneously
40 = a+5d
-16 = a+19d
Subtracting both equation
40-(-16) = 5d-19d
56 = -14d
d = 56/-14
d = -4
Substituting d = -4 into equation
a+5d = 40
a+5(-4) = 40
a-20 = 40
a = 20+40
a = 60
Given a = 60, d = -4, to get the nth term of the sequence:
Tn = a+(n-1)d
Tn = 60+(n-1)(-4)
Tn = 60+(-4n+4)
Tn = 60-4n+4
Tn = 64-4n
(10)2 x (6)3 = 38
It will cost $38 for 2 adult's and 3 children's tickets.
