Answer:
f(8) = -9
Step-by-step explanation:
Substitute 8 in for x.
f(8) = -2(8) + 7
f(8) = -16 + 7
f(8) = -9
7^2 = 6^2 + 9^2 - 2(6)(9)cos(m)
-68 = 2(6)(9)cos(m)
cos(m) = -0.6296
m = arcos ( -0.6296)
m = 129.0 degrees
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11 1/7 mixed number
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