c^2 = a^2 + b^2 - 2*ab*Cos(C)
c = 16; a = 17; b = 8 (what you call a and b don't really matter. c does). Substitute.
16^2 = 17^2 + 8^2 - 2*17*8*Cos(C) Add the first 2 on the right.
256 = 289 + 64 - 282*cos(C)
256 = 353 - 282*cos(C)
Whatever you do, don't do any more combing on the right side. Subtract 353 from both sides.
-97 = -282 * cos(C )
Divide by 282
0.34397 = cos(C)
cos-1(0.34397) = C ; C = 69.88 degrees.
Do you need more help on this question? All of these are done the same way.
1 milligram = 1/1000 gram
Therefore:
500 milligrams = 500/1000 gram = 1/2 gram
500 half grams fit into 250g, as 500 * 1/2 gram = 250 grams.
Therefore, there are 500 vitamin C tablets in the bottle.
8, 16, 24, 32, 40, 48, 56, 64, 72, 80, 88, 96, 104
The answer is x=-5 and x=1
Explanation: you just look where the line crosses the x axis which is left to right
