
John M. answered 03/29/20
Math Teacher/Tutor/Engineer - Your Home, Library, MainStreet or Online
I let ∠A = 90°, so ∠C = 55º This seems too easy, but it works.
Since BC = 3x, AC/3x = Sin(35º) and AC = 1.72x. Then AB/3x = Cos(35º) and AB = 2.46x
Using the Pythagorean Theorem, √[(2.46x)2 + (1.72x)2 ] = 3x which is BC.