Question

DEF is shown on the coordinate plane below.

D(-9,8)
E(9,5)
F(-5,-9)
What is the perimeter of DEF? If necessary, round your answer to the nearest tenth.

Answer 1

55.5

Explanation:

`DE=√((-9-9)^2+(8-5)^2)=√(333) \\ \\ DF=√((-9-(-5))^2+(-9-8)^2)=√(305) \\ \\ EF=√((-5-9)^2+(-9-5)^2)=√(392)`

The perimeter is thus
`√(333)+√(305)+√(392) \approx 55.5`.