Question

PLease help me it says use cosine law

Answer 1

Answer:

59 degrees

Step-by-step explanation:

law of cosines states that

for sides A B C and angle c opposite to side C,

$C = \sqrt{A^2 + B^2-2ABcos(c)} \\cos(c) = \frac{c^2-a^2-b^2}{-2ab}$

cos(b) = $\frac{13^2-6^2-15^2}{-2(6)(15)} = 23/45$

cos-1(23/45) = b

b = 59

Answer 2

Answer:59

Step-by-step explanation:

C2=a2+b2-2ab cosC

13x13=15x15+6x6-2(15)(6)cosC

169=225+36-180cosC

169=261-180cosC

-92=180cosC

-92/-180=cosC

C=arccos92/180. On your calculator it will say cos-1

C=59.23 or m<B = 59. Rounded to the nearest degree.