Janelle S. answered • 09/24/20

Penn State Grad for ME, Math & Test Prep Tutoring (10+ yrs experience)

X(−3, −6), Y(21, −6), and Z(21, 4)

Use the distance formula to find the length of each side:

distance = √[(x_{2} - x_{1})^{2} + (y_{2} - y_{1})^{2}]

XY = √[(21 - (-3))^{2} + ((-6) - (-6))^{2}] = √(24^{2} + 0^{2}) = √576 = 24

YZ = √[(21 - 21)^{2} + ((4) - (-6))^{2}] = √(0^{2} + 10^{2}) = √100 = 10

XZ = √[(21 - (-3))^{2} + ((4) - (-6))^{2}] = √(24^{2} + 10^{2}) = √676 = 26

perimeter = XY + YZ + XZ = 24 + 10 + 26 = 60