I think it is b
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Literally y is across from 112, so y=112
Answer:
how many miles did she travel each hour? Then I can answer your question
Let cos x = a, then
2a^2 + a - 1 = 0,
solving the quadratic equation, we have:
a = 0.5 or -1.
i.e. cos x = 0.5 or cos x = -1
for cos x = 0.5,
x = pi/3, 2pi - pi/3 = pi/3, 5pi/3
for cos x = -1,
x = pi
therefore, x = pi, pi/3, 5pi/3
Answer: B
Options in 3rd and 4th questions are wrong!. Hope it helps :)