The common difference is x
the first term is x+1
a_8 = x+1 + x(8-1) = x+1 + 7x = 8x + 1
first step is to subtract 21 from both sides
2m+21-21=3-21
2m=-18
2m/2 and -18/2
m=-9
So the final answer is m=-9 (negative nine equals m)


The basic angle for 1/2 is 60°, and cosines are negative in the first and third quadrant.
So, you take 180° - 60° = 120° to get the angle in the first quadrant, and 180° + 60° = 240° to get the angle in the third quadrant.
Since only 120° is an option, the answer is
B.
29/5 is 5.8 5.8 dividen by 9 1/2 is 0.61052631578
Hope this helps! Have a great day!!!