Equilateral triangle solve
EF = FD = DE
ZA = 3X
FZ = 2X + 8
APPLY formula for h, height of triangle equilateral
h = (1/2)• FD • √3
h also is equatl to FZ + ZA = (2x + 8)+ (3x) = 5x + 8
Therefore
FD = 2h/ (√3)
FD = 2• (5x + 8)/√3
So then finally
PART A
ZA = 1/3 FA
ZF = 2/3 FA
Therefore ZF/ZA = 2
This means equation to solve x is
ZF = 2ZA
2x + 8 = 2•3x
its. OPTION A
PART B
Length of FA = FZ + FA = 2x + 8 + 3 x
its OPTION B
PART C
Lenght of FA
x = 8/4 = 2
FA = 8 + 5 x = 18
its OPTION C