N. 231

a)

$b=\sqrt{d^2-h^2}=\sqrt{12,5^2-10^2}=\sqrt{156,25-100}=\sqrt{56,25}=7,5~dm$

$B+b=\frac{2*A}{h}=\frac{2*195}{10}=39~dm$

$B=(B+b)-b=39-7,5=31,5~dm$

b)

$D=\sqrt{h^2+B^2}=\sqrt{10^2+31,5^2}=\sqrt{100+992,25}=\sqrt{1092,25}=33~dm$

c)

La proiezione del lato obliquo sulla base maggiore misura:

$p_l=B-b=31,5-7,5=24~dm$

$l=\sqrt{h^2+p_l^2}=\sqrt{10^2+24^2}=\sqrt{100+576}=\sqrt{676}=26~dm$

$p=B+b+h+l=39+10+26=75~dm$