use strict;  
use warnings;
use Data::Dumper;

my %coordinates;
$coordinates{A} = [0,0];
$coordinates{B} = [0,90];

while (<DATA>) {
	my ($site, $dA, $dB, $dC) = /(\w):\s+(\d+)\s+(\d+)\s+(\d+)/;
	$coordinates{$site} = find_coord ($dA, $dB, $dC);
}
print Dumper \%coordinates;

sub find_coord {
	my ($a, $b, $c) = @_;
	my $sq_dist_dif = $a*$a - $b*$b;
	my $y = $sq_dist_dif/(90*2) + 90/2;
	my $x = sqrt ($a*$a - $y*$y);
	return [$x, $y] unless $c;
	my $dist_2_c_1 = distance ([$x, $y], $coordinates{C}, $c);
	my $dist_2_c_2 = distance ([-$x, $y], $coordinates{C}, $c);
	$dist_2_c_1 < $dist_2_c_2 ? [$x, $y, $dist_2_c_1] : [-$x, $y, $dist_2_c_2];
}
sub distance {
	return abs (sqrt (($_[0][0] - $_[1][0])**2 + ($_[0][1] - $_[1][1])**2) - $_[2]);
}

__DATA__
C: 64  76  0
D: 28  70  74
E: 120  62  68
F: 68  52  93
G: 53  125 64