document.write( "Question 791782: What would be the easiest way to solve this problem ? The only known value is that z=9\r
\n" ); document.write( "\n" ); document.write( "x + Y + Z = 14
\n" ); document.write( "x - 2y = -4
\n" ); document.write( "Z = 9 \n" ); document.write( "
Algebra.Com's Answer #479721 by rothauserc(4718)\"\" \"About 
You can put this solution on YOUR website!
What would be the easiest way to solve this problem ? The only known value is that z=9
\n" ); document.write( "*****from this statement and the given equations, one can assume without loss of generality that you meant z is equivalent to Z in this problem and Y is equivalent to y although in mathematics one must be consistent :-) *******\r
\n" ); document.write( "\n" ); document.write( "we are given
\n" ); document.write( "x + Y + Z = 14
\n" ); document.write( "x - 2y = -4
\n" ); document.write( "Z = 9
\n" ); document.write( "substitute for z in equation 1, this gives us two equations in two unknowns
\n" ); document.write( "x +y +9 = 14
\n" ); document.write( "x -2y = -4
\n" ); document.write( "subtract 9 from both sides of =
\n" ); document.write( "x +y = 5 and
\n" ); document.write( "x = 5 -y
\n" ); document.write( "substitute for x in the second equation
\n" ); document.write( "5 -y -2y = -4
\n" ); document.write( "subtract 5 from both sides of =
\n" ); document.write( "-3y = -9
\n" ); document.write( "y = 3
\n" ); document.write( "x +3 = 5
\n" ); document.write( "x = 2
\n" ); document.write( "check with second equation
\n" ); document.write( "2 -2*3 = -4
\n" ); document.write( "-4 = -4
\n" ); document.write( "answers check
\n" ); document.write( "x = 2, y = 3 \n" ); document.write( "
\n" );