Angle at point A = 180 - 90 - 40 = 50 degrees
To find 2 remaining lengths of sides of triangle we just need to use basic trigonometry.
cos40 = 10/AC => AC = 10/cos40 = 13.05
tan40 = AB/10 => AB = 10*tan40 = 8.39
If we want to check this we can use Pythagoras theorem:
AB^2 + BC^2 = AC^2 and see that lengths that we calculated are correct.
