Tolong bantuan nya ya

DG^2=EG x GF
<=> 8^2=5 x GF
<=> 64=5 x GF
<=> GF= 64/5
<=> GF = 12,8 cm

luas segitiga DEF
= 1/2 x EF x DG
= 1/2 x (5+12,8) x 8
=1/2 x 17,8 x 8
= 1/2 x 142,4
= 71,2 cm^2