Réponse :
rappel : V = 1/3(aire base *h)
V IBHG = 1/3(IF*FB)/2*FG)=1/3[(5*5/2)/2*5]=10,41++.. = 10,41cm^3
V IEAH =1/3(IE*EA)/2*5= V IBHG=10,41cm^3
V prisme = (BC*GC)/2*h = (5*5)/2*5=62,5cm^3
2) V IABGH = V cube-V(IBHG+IEAH+ADHGCB)=
5^²-(10,41+10,41+62,5)=
125-83,32=41,68cm^3
3) on connait le V
base = ABHG
A base = AB*BG
on connait AB,
on calcule BG :
BG²=5²+5²=50
BG=√50=5√2
A ABGH = 5*5√2 = 25√2
V = 41,68cm^3
A base = 25√2
h = V IABGH/3*A ABGH
h= 41,68/3*25√2=41,68/75√2=0,39283....=0,40cm
si tu veux des explications demande,
