Answer:
r=3 ft
Step-by-step explanation:
it is similarity of two triangles
one
perpendicular side=10 ft
base=10/2=5 ft
second
perpendicular side=10-4=6 ft
Base r=?

Subtract what is to the right of the equal sign form both side of the equation but any way the answer is 0
7623, 27.8, 76.9, and 8401 it is really simple just use a calculator........