se poate cu materiade liceu cu teorema sinusului
notand cu a, b, c, laturile care se opun unghiurilor A, B si ,respectiv C, avem:
a/sinA=b/sinB=c/sinC=2R
a/sin30°=b/sin45°=c/sin105°=24√2
a=24√2sin30°=24√2*1/2=12√2
b=24√2sin45°=24√2*√2/2=24
c=24√2sin105°
sin105°=sin60°cos45°+sin45°cos60°=(√2/2)*(√3/2+1/2)= (√6+√2)/4
c=24√2*(√6+√2)/4=6√2(√6+√2)=6*2(√3+1)=12(1+√3)
Perim=a+b+c=12√2+24+12+12√3=(36+12(√2+√3))cm
A=abc/4R=12√2*24*12(1+√3)/12√2=24*12(1+√3)=288(1+√3)cm²