document.write( "Question 530055: when solving 3x + 6 = 18, why do you add -6 under the 6 which makes 0 and add -6 under the 18, which makes 12? then it turns out to be 3x = 12, and x = 4. The problem I am having is the signs, why do you use the negative 6? \n" ); document.write( "
Algebra.Com's Answer #349866 by rfer(16322)![]() ![]() ![]() You can put this solution on YOUR website! In order to remove the 6 from the left side it is necessary to do the opposite of what is there. In this case it is a +6 so you need to subtract to remove it. \n" ); document.write( "In equations it is always necessay to do the same thing to both sides, thus 18-6=12. \n" ); document.write( "Another thought, if you had 3x-6=18 you would add 6 to both sides to remove it from the left side. Always do the opposite to what is there. \n" ); document.write( "Does that help? \n" ); document.write( "Bob \n" ); document.write( " |