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You can put this solution on YOUR website!
So 11 - c >= 8. Just treat the >= like an equals sign and perform \"normal algebra\" but watch out! There's a trick here!\r
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\n" ); document.write( "\n" ); document.write( "OK. At the end, we usually like the variable to be on the left side, and the single number to be on the right. We'll do that. To get the c by itself, we must subtract 11 from both sides first. That gives us:\r
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\n" ); document.write( "\n" ); document.write( "-c >= -5.\r
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\n" ); document.write( "\n" ); document.write( "Here's where it gets wacky. There is a rule, and you better know it because it's the one most of us forget. When we multiply an inequality with a negative number on both sides, we FLIP the inequality. We don't like the c to have a negative sign in front of it. After all, we're after c, not -c. So we need to multiply both sides by -1:\r
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\n" ); document.write( "\n" ); document.write( "c <= 5. <---- multiplying by a negative number flips the sign of the inequality.\r
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\n" ); document.write( "\n" ); document.write( "For real, why does it happen? That's because the negative side of the number line is a mirror reflection of the positive side. A big number with a negative sign in front of it really is of less value than a small number with a negative sign on it. It's the opposite for positive numbers!\r
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\n" ); document.write( "\n" ); document.write( "Check out the simple inequality -5 < -1. We agree that -5 is way to the left of -1 on the number line, causing it to be less than -1. When you multiply both sides by -1, you'll end up (for now) with 5 < 1 which is FALSE!. The way to fix that is to flip the inequality from < to >, so now, 5 > 1 which is TRUE! \n" ); document.write( "