rad7^2=7 rad(-10)^2=-10
rad9^2=9 rad(-16)^2=-16
rad15^2=15 rad(-30)^2=-30
rad20^2=20 rad(-45)^2=-45
a. 1+2+...+8=36,este patrat perfet
b.11+12+...+16=81 este patrat perfect
c.9^2+12^2=81+144=225,este patrat perfect
d.7^2+24^2=49+576=625,este patrat perfect
