To solve number 14, we will make use of the Law of Cosines, which states that:
[tex]=\sqrt[]{^2+^2^{}-2\cos}[/tex]
As in our problem b = 15, c = 13 and A = 95°,we can replace these values in the formula and solve for a:
[tex]=\sqrt[]{15^2+13^2-2\cdot(15\cdot13)\cos 95}[/tex][tex]=\sqrt[]{15^2+13^2-390\cos 95}[/tex][tex]a\approx20.69[/tex]
In our case, a is the segment BC.
Answer: 20.7
