Given the triangle below, what is the length of the third side, rounded to the nearest whole number?

Question

asked Apr 25, 2018 129k views

2 Answers

Thatgibbyguy · Answer 1 · 2018-04-30T13:22:15+0000

Answer:

the length of third side is 16.

Explanation:

We can use Law of Cosine to find the third side of the triangle.

Law of Cosine is given by

$a^2=b^2+c^2-2bc\cosA$

Substituting the known values, we get

$a^2=12^2+19^2-2\cdot12\cdot19\cos56$

On simplifying, we get

$a^2=505-456\cos56\\\\a^2=250.008\\\\a=15.81$

When rounded to nearest whole number, the length of third side is 16.