Question

What is the perimeter of △DEF to the nearest tenth?

Answer 1

Answer:

The perimeter of △DEF 43

Step-by-step explanation:

Sin A/ a = Sin B / b = Sin C/ c

sin D/ d =

Sin E / e = sin F /f

sin 52/ e = sin 90 / 18

e =  18 x sin 52 / sin 90

e = 14.184 /1

e = 14.2

From phythagoras theorem ,

/hyp/² = /opp/² + /adj/²

18² = 14.2² + /adj/²

/adj/²= 18² - 14.2²

/adj/² = 324 + 201.64

/adj/² = 119.51

/adj/ = √122.36

        = 11.1

Perimeter of Triangle = a + b +c

where a = side

            b = base

            c = side

Perimeter = 18 + 11.1 + 14.2

Perimeter = 43.3

Perimeter= 43