#!/usr/bin/perl
# line.pl - Don Yang (uguu.org)
# Solve linear interpolation
#
# 05/21/03

print "t1 = ";       $t1 = <STDIN>;
print "t2 = ";       $t2 = <STDIN>;
$t1 += 0.0;
$t2 += 0.0;
print "f($t1) = ";   $y1 = <STDIN>;
print "f($t2) = ";   $y2 = <STDIN>;

$a = ($y1 - $y2) / ($t1 - $t2);
$b = $y1 - $a * $t1;
print "a = $a, b = $b\n";