Answer:
Step-by-step explanation:
coordinates of A,B,C are A(5,15),B(15,5),C(20,10)
AB=√((15-5)²+(5-15)²)=√(100+100)=√200=10√2
BC=√((20-15)²+(10-5)²)=√(25+25)=√50=5√2
AC=√((20-5)²+(10-15)²)=√(225+25)=√250=5√10
Perimeter=10√2+5√2+5√10=15√2+5√10≈37 units
