View of /trunk/NationalProblemLibrary/Rochester/setAlgebra14Lines/lh2-1_9.pg

    1 ##DESCRIPTION
    2 ##   Algebra: Lines
    3 ##ENDDESCRIPTION
    4 
    5 ##KEYWORDS('Algebra', 'Lines')
    6 ##Tagged by up2p
    7 
    8 ##DBsubject('Algebra')
    9 ##DBchapter('Coordinates and Graphs')
   10 ##DBsection('Lines')
   11 ##Date('')
   12 ##Author('')
   13 ##Institution('Rochester')
   14 ##TitleText1('')
   15 ##EditionText1('')
   16 ##AuthorText1('')
   17 ##Section1('')
   18 ##Problem1('')
   19 
   20 DOCUMENT();        # This should be the first executable line in the problem.
   21 
   22 loadMacros(
   23 "PG.pl",
   24 "PGbasicmacros.pl",
   25 "PGchoicemacros.pl",
   26 "PGanswermacros.pl",
   27 "PGauxiliaryFunctions.pl",
   28 "PGgraphmacros.pl",
   29 "extraAnswerEvaluators.pl"
   30 
   31 );
   32 
   33 TEXT(beginproblem());
   34 $showPartialCorrectAnswers = 1;
   35 
   36 $x1 = non_zero_random(-5,6,1);
   37 $y1 = non_zero_random(-5,6,1);
   38 
   39 $graph = init_graph(-10,-10,10,10,'axes'=>[0,0],'grid'=>[20,20],'size'=>[200,200]);
   40 $aline = FEQ("(-$y1/$x1)*x+$y1 for x in <-10,10> using color:green and weight:2");
   41 
   42 plot_functions($graph,$aline);
   43 
   44 BEGIN_TEXT
   45 
   46 Find an equation \(y=mx+b\) for the line whose graph is sketched
   47 $BR$BR \{ image(insertGraph($graph), width=>200, height=>200) \}
   48 $BR$BR
   49 The slope \(m\) equals  \{ans_rule(10)\}.
   50 $BR
   51 The \(y\)-intercept \(b\) equals  \{ans_rule(10)\}.
   52 END_TEXT
   53 
   54 $ans1 = -$y1/$x1;
   55 $ans2 = $y1;
   56 
   57 ANS(num_cmp($ans1));
   58 ANS(num_cmp($ans2));
   59 
   60 ENDDOCUMENT();        # This should be the last executable line in the problem.