%%HP: T(1)A(D)F(.);
 { {
"HALLAR EL ANGULO AGUDO DEL"
"PARALELOGRAMA CUYOS VERTICES"
"SON A(-2,1),B(1,5),C(10,7),"
"D(7,3)."
"M1=3-1/7-(-2)=2/9"
"M2=5-1/1-(-2)=4/3"
"TAG=M2-M1/1+M2M1"
"    =(4/3-2/9)/1+(4/3)(2/9)"
"    =6/7.  "
"=ARC TAG 6/7=40.6"
} } HELP.3

