document.write( "Question 24726: solve algebraically for the value of x where these two lines cross:3y=21-6x and 3y=24-9x (show work) \n" ); document.write( "

Algebra.Com's Answer #13190 by rapaljer(4671) $\"\"$ $\"About$

You can put this solution on YOUR website!
Since you have \"3y = ___\" in both equations, and since the instructions say to solve algebraically for x, just set them equal to each other, and solve for x:\r
\n" ); document.write( "\n" ); document.write( "3y = 3y
\n" ); document.write( "21-6x = 24- 9x \r
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\n" ); document.write( "\n" ); document.write( "Add +9x to each side to get the x terms on the left side:
\n" ); document.write( "21 -6x + 9x = 24 - 9x + 9x
\n" ); document.write( "21+3x = 24\r
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\n" ); document.write( "\n" ); document.write( "Next, subtract 21 from each side:
\n" ); document.write( "21-21 + 3x = 24 - 21
\n" ); document.write( "3x = 3\r
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\n" ); document.write( "\n" ); document.write( "Divide both sides by 3:
\n" ); document.write( "x = 1.\r
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\n" ); document.write( "\n" ); document.write( "Check your answer:
\n" ); document.write( "21 - 6x = 24-9x
\n" ); document.write( "21 -6(1) = 24 - 9(1)
\n" ); document.write( "15 = 15 \r
\n" ); document.write( "\n" ); document.write( "It checks!\r
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\n" ); document.write( "\n" ); document.write( "R^2 at SCC \n" ); document.write( "

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