document.write( "Question 1130652: Solve the system using any method. (Simplify your answer completely. If the system is dependent, enter a general solution in terms of x and y. If there is no solution, enter NO SOLUTION.)\r
\n" ); document.write( "\n" ); document.write( "5x − 2y = 22
\n" ); document.write( "y= 5/2 x - 11
\n" ); document.write( "

Algebra.Com's Answer #747293 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
\r
\n" ); document.write( "\n" ); document.write( "\"5x+-+2y+=+22\"
\n" ); document.write( "\"y=+%285%2F2%29+x-11\"
\n" ); document.write( "--------------------\r
\n" ); document.write( "\n" ); document.write( "\"5x+-+2y+=+22\"
\n" ); document.write( "\"-%285%2F2%29+x%2By=+-11\"\r
\n" ); document.write( "\n" ); document.write( "\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: Solving a System of Linear Equations by Elimination/Addition

\n" ); document.write( "
\n" ); document.write( " \"%28-5%2F2%29%2Ax%2B%281%29%2Ay=-11\" Start with the second equation
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"2%28%28-5%2F2%29%2Ax%2B%281%29%2Ay%29=%282%29%2A%28-11%29\" Multiply both sides by the LCD 2
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"-5%2Ax%2B2%2Ay=-22\" Distribute and simplify
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " -----------------------------------------
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " Lets start with the given system of linear equations
\n" ); document.write( "
\n" ); document.write( " \"5%2Ax-2%2Ay=22\"
\n" ); document.write( " \"-5%2Ax%2B2%2Ay=-22\"
\n" ); document.write( "
\n" ); document.write( " In order to solve for one variable, we must eliminate the other variable. So if we wanted to solve for y, we would have to eliminate x (or vice versa).
\n" ); document.write( "
\n" ); document.write( " So lets eliminate x. In order to do that, we need to have both x coefficients that are equal but have opposite signs (for instance 2 and -2 are equal but have opposite signs). This way they will add to zero.
\n" ); document.write( "
\n" ); document.write( " So to make the x coefficients equal but opposite, we need to multiply both x coefficients by some number to get them to an equal number. So if we wanted to get 5 and -5 to some equal number, we could try to get them to the LCM.
\n" ); document.write( "
\n" ); document.write( " Since the LCM of 5 and -5 is -5, we need to multiply both sides of the top equation by -1 and multiply both sides of the bottom equation by -1 like this:
\n" ); document.write( "
\n" ); document.write( " \"-1%2A%285%2Ax-2%2Ay%29=%2822%29%2A-1\" Multiply the top equation (both sides) by -1
\n" ); document.write( " \"-1%2A%28-5%2Ax%2B2%2Ay%29=%28-22%29%2A-1\" Multiply the bottom equation (both sides) by -1
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " So after multiplying we get this:
\n" ); document.write( " \"-5%2Ax%2B2%2Ay=-22\"
\n" ); document.write( " \"5%2Ax-2%2Ay=22\"
\n" ); document.write( "
\n" ); document.write( " Notice how -5 and 5 add to zero, 2 and -2 add to zero, -22 and 22 and to zero (ie \"-5%2B5=0\") \"2%2B-2=0\", and \"-22%2B22=0\")
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " So we're left with
\n" ); document.write( "
\n" ); document.write( " \"0=0\"
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " which means any x or y value will satisfy the system of equations. So there are an infinite number of solutions
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " So this system is dependent
\n" ); document.write( "
\n" ); document.write( "
\n" );