There are two buildings bisede each ather that are 47feet and 31 feet high. the buildings are 12 feet apart. what is the distance between the rooftop of the bluilfings

You use Pythagorean theorem...a^2+b^2=c^2
a=12ft
b=47-31.. height of the triangle
c=distance between two roof tops

(12)^2+(16)^2=c^2
144+256=c^2
400=c^2, take square root of both sides
c=20ft