Answer:
Part A
5yr old boy.
Y=-(1/8)x+113/8 x=5
Y=-5/8+113/8=(113-5)/8=108/8
Y=13.5 hrs
Yes the estimated value of sleep by this function is reasonable as it is close to childhood more sleep is likely.
Part B
20yr old boy.
Y=-(1/8)x+113/8 x=20
Y=-20/8+113/8=(113-20)/8=93/8
Y=11.63 hrs
No the estimated value of sleep by this function is not reasonable as the normal sleep of 7-8 hrs is enough for adults.
Step-by-step explanation:
Awnser is below in the photo
You can distribute the q to both terms to get

Fron the table given:
A3 = 112,
A8 = - 3,584
An = A1 *r ^ (n-1)
=> A3 = A1 (r^2) = 112
A8 = A1(r^7) = - 3,584
=> - 3584 / 112 = (r^7) / (r^2)
=> (r^5) = - 32
=> r = - 2
=> A1 (- 2)^2 = 112
=> A1 = 112 / 4 = 28
Answer: a1 = 28