Question

Problema 1
va rog
dau coroana
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Answer 1

Răspuns:

a) A(∆ABC)=60√3cm²

b) A(∆ABC)=30cm²

c)A(∆ABC)≈26,14cm²

Explicație pas cu pas:

a)

A(∆ABC)=1/2*AB*BC*sin<B

sin60°=√3/2

A(∆ABC)=1/2*12*10*√3/2=60√3 cm²

b)

A(∆ABC)=1/2*AC*BD=1/2*10*6=30cm²

c)

A(∆ABC)=√((p(p-AB)(p-AC)(p-BC))

p=(AB+AC+BC)/2=(6+9+12)/2=27/2=13,5cm

A(∆ABC)=√((13,5(13,5-6)(13,5-9)(13,5-12))=

=√(13,5*7,5*4,5*1,5)=√683,4375≈26,14cm²