Răspuns:
Explicație pas cu pas:
a)
AC² =BC²-AB²²-18²=900-324=576
AC=√576 =24cm
AB²=BD*CD
18²=BD*30
BD=324/30=10.8 cm
CD=BC-BD =30-10.8 =19.2 cm
AC²=BC²-AB²=30²-18²=900-324 =576
AC=√576 =24 cm
AD =AB*AC/BC=18*24/30=14.4 cm
b)
AB²=BD*BC
60²=36*BC
BC=3600/36 =100 cm
CD=BC-BD=100-36=64 cm
AD²=BD*CD=36*64=2304
AD=√2304 =48cm
AC²=BC²-AB²=100²-60²=10000-3600=6400
AC=√6400=80 cm