Answer:
the answer is any number above 18
For Samantha, 2 tick marks east is 120 units east because 1 tick is 60 units.
For Ryu, 8 tick marks west is 480 units west because 1 tick is 60 units.
They are walking to form a line. Just add their distances from 0.
120 + 480 = 600.
--------------------------0----------------------------
Ryu: 480 Samantha: 120
480 + 120 = 600.
600 units, or feet.
The wording of this question is a bit confusing... You can't write a sequence in sigma notation, but rather a series or sum. I think the question is asking you to write the sum of the sequence,

which would be

in sigma notation.
To do this, notice that the denominator in each term is a power of 2, starting with
and ending with
. So in sigma notation, this series is

Answer is going to be x>-19
Answer:
15x+45-2x=15x-2x-10
13x+45=13x+10
13x-13x=10-45
if you simplify further
you will not get an answer there is a mistake in the question