document.write( "Question 100064This question is from textbook Thinking Mathematically
\n" ); document.write( ": the problem is
\n" ); document.write( "2x+3y=11
\n" ); document.write( "x-4y=0
\n" ); document.write( "I cannot figure out what to do with the x in the sescond equation. \n" ); document.write( "

Algebra.Com's Answer #72862 by Adam(64) $\"\"$ $\"About$

You can put this solution on YOUR website!
This is a system of 2 linear equations with two variables. You can, for instance, express the x from second equation(in terms of y) and substitute it into first equation - thus you'll get linear equation with one variable.Which you can easily solve and substituting answer into any of the original equations get the rest of the solution.\r
\n" ); document.write( "\n" ); document.write( "2x+3y=11
\n" ); document.write( "x-4y=0 /+4y
\n" ); document.write( "x=4y\r
\n" ); document.write( "\n" ); document.write( "2x+3(4y)=11
\n" ); document.write( "2(4y)+3y=11
\n" ); document.write( "8y+3y = 11
\n" ); document.write( "11y = 11
\n" ); document.write( "y = 1\r
\n" ); document.write( "\n" ); document.write( "now we can substitute into any equation
\n" ); document.write( "i.e.: 2x+3(1)=11
\n" ); document.write( "2x+3 = 11 /-3
\n" ); document.write( "2x = 8 /:2
\n" ); document.write( "x = 4\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "after plotting it looks like this:
\n" ); document.write( " $\"+graph%28+400%2C+300%2C+-5%2C+10%2C+-5%2C+10%2C+x%2F4%2C+%2811-2%2Ax%29%2F3%29+\"$ \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

\n" );