Given the dimensions of triangle ABC:
AB = 5
BC = 8
AC = 7
Let's determine the largest angle of triangle ABC.
We have a sketch of the triangle below:
In a triangle, the largest angle is the angle opposite the side with the largest side length.
From the given triangle ABC, the largest side is BC = 8.
The angle which is opposite BC is angle BAC.
Therefore, the largest angle of △ABC is ∠BAC