perl program

[9875]

I need a solution for 2 equations with 2 unknowns
It can be done mathematically but putting it into the code is tough. ANy help is appreciated.
here is some test data

2x -3y = -8
x + y =6
(2,4)

4x - 2y = -28
-0.5x + y = 5
(-6,2)

 

[tchatzi]

you want to make a program that can solve whatever
'2 equations with 2 unknows' problem?

and if yes

you know that even with 2 unknowns, someone can make a realy difficult problem to solve, and realy complex.

or you just want to print the resolts from those two you just wrote?

the program you want to make will take any input from the command line and if yes what?

we have to know what exactly you want to make

 

[varakal]

This is not that difficult.
my ($x1, $y1, $c1);
my ($x2, $y2, $c2);

$y = (($c2*$x1) - ($c1*$x3)) / (($y2*$x1) - ($y1*$x3));
Then calculate $x similarly.

 

[varakal]

Sorry, $x3 should be $x2.

my ($x1, $y1, $c1);
my ($x2, $y2, $c2);

$y = (($c2*$x1) - ($c1*$x2)) / (($y2*$x1) - ($y1*$x2));
Then calculate $x similarly.

 

[cntr]

Ruby:

def solve( *eqs )
  ary = []
  eqs.each { |x|
    # Remove spaces.
    x.gsub!( /\s+/, "")
    # If variable lacks coefficient, use 1.
    x.gsub!( /(\d*\.?\d*)[xy]/ ) {|m| m="1"+m if ""==$1; m}
    ary << x.split( /[xy=]+/ )
  }
  # Remove +'s and convert strings to floats.
  ary.map!{|row| row.map!{|s| s.sub(/\+/,"")
    s.to_f  }}
  p ary
  mul = ary[0][1] / ary[1][1] * -1
  ary[1].map!{ |f| f*mul }
  x = (ary[0][2]+ary[1][2])/(ary[0][0]+ary[1][0])
  y = (ary[0][2]-ary[0][0]*x)/ary[0][1]
  [x, y]
end

x,y = solve( "2x -3y = -8", "x + y =6" )
printf "%g,%g\n", x, y

x,y = solve( "4x - 2y = -28", "-0.5x + y = 5" )
printf "%g,%g\n", x, y

The output is
[tt]
[[2.0, -3.0, -8.0], [1.0, 1.0, 6.0]]
2,4
[[4.0, -2.0, -28.0], [-0.5, 1.0, 5.0]]
-6,2
[/tt]