Triangle RST has vertices at R(-4,7), S(-6,3) and T(-2,3). Jennifer believes that the perimeter of ΔRST is 26 square units. Why is Jennifer incorrect?

Answer 1

Length of ST = 4

Length of RS = √[(-6-(-4))² + (3-7)²] = √20

Length of RT = √[(-2-(-4))² + (3-7)²] = √20

Perimeter = 4 + 2√20 = 4 + 4√5 units

Answer 2

-6-(-2)=-4/2=2(7-3)=8sq/in