The sequence: a 1 = - 4, a 2 = 8, a 3 = -16,...
a 2 = a 1 * r
8 = - 4 * r
r = 8 : ( - 4 )
r = - 2
a n = a 1 * r^(n-1)
a 5 = - 4 * ( - 2 ) ^4 = - 4 * 16 = - 64
Answer:
The fifth term in the sequence is - 64.
Abd is a right angled triangle so by pythagoras we know

and to calculate h we need to use the sine rule

i hope this helps
Ur output value is f(x).....so to do this problem u need to sub in 2/3 for f(x) and solve for the input value which is x
f(x) = -1/3x + 7
2/3 = -1/3x + 7 ...multiply everything by 3
2 = -x + 21
2 - 21 = - x
- 19 = -x
19 = x <== ur output