
Mark M. answered 11/27/23
I love tutoring Math.
You have three points, uppercase A, B, C, which are the vertices of a triangle.
As usual, the length of side AB is called lowercase c, the length of side BC is called a,
and the length of side AC is called b.
We want to find the length of side AB (also known as c).
Draw a picture of the above triangle.
You said that angle CAB is 49.5°. You also said that angle CBA is 49.5°.
I believe you mean to say that angle ACB (also known simply as angle C) is 49.5°.
Write the 49.5° at angle C of the triangle.
I believe you mean to say that the length of side AC (also known as b) is 365 yards.
I believe you mean to say thatthe length of side BC (also known as a) is 502 yards.
Write these numbers along sides b and a.
Now, to find the length of side AB (also known as c), use the Law of Cosines:
c2 = a2 + b2 - 2 ab cos c.
Substituting in the numbers we were given,
c2 = 3652 + 5022 - 2 times 365 times 502 times cos 49.5°
Doing the arithmetic,
c2 = 133225 + 252004 - 366460 times 0.64944
c2 = 385229 - 237993.7824
c2 = 147235.2176
Taking square roots on both sides,
c = 383.7124 yards is the distance from A to B.
If triangle ABC had been a right triangle, we could have used the Pythagorean theorem c2 = a2 + b2 to get the length of side AB (also known as c). But it's not a right triangle, so we had to resort to the similar but more complicated Law of Cosines. Good luck.