The lengths of the three sides of a triangle (not necessarily a right triangle) are 3.10 meters, 8.03 meters and 9.29 meters. what is the cosine of the angle opposite the side of length 9.29 meters

The law of cosines tells you
.. 9.29^2 = 3.10^2 +8.03^2 -2*3.10*8.03*cos(angle)
.. cos(angle) = (9.29^2 -3.10^2 -8.03^2)/(-2*3.10*8.03)
.. cos(angle) ≈ -0.245314

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The angle is approximately arccos(-0.245314) ≈ 104.20039°, verified by a triangle solver.

Yes you are right the correct answer is b

Do the math. she originally had 50 dollars on her gift card and she had 12 dollars left on her gift card after she finished her shopping spree. if you subtract 50 minus 12 you get thirty eight dollars as your answer. so therefore, ciara spent 38 dollars total o