document.write( "Question 285345: im a little confused as to what to do with the exponent in this situation. My teacher taught us in class but now that im home my mind went blank. The answer i came up with is -1. But the answers that were provided on this site are -2 and -4. Here is the problem: x^2 + 6x + 8 = 0 Here's what i did: x*x+6x+8=0 2x+6x+8=0 8x+8=0 8x=-8 x=-1...Someone just sent me an answer that just said factor (x+4)(x+2)=0....I'm even more confused now...IS THERE ANYONE THAT CAN BREAK THIS PROBLEM DOWN FOR ME STEP BY STEP PLEASE...THANK YOU!! \n" ); document.write( "
Algebra.Com's Answer #206865 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
You made an error in thinking that \"x%2Ax=2x\". This is NOT true, and is a big misconception. So \"x%2Ax%3C%3E2x\" for all 'x'. What you were thinking of (I think) is that \"x%2Bx=2x\" which is true for all 'x'.\r
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\n" ); document.write( "\n" ); document.write( "There are two ways to solve this problem.\r
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\n" ); document.write( "\n" ); document.write( "# 1 Factoring\r
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\n" ); document.write( "\n" ); document.write( "First factor \"x%5E2+%2B+6x+%2B+8\"\r
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\n" ); document.write( "\n" ); document.write( "Looking at the expression \"x%5E2%2B6x%2B8\", we can see that the first coefficient is \"1\", the second coefficient is \"6\", and the last term is \"8\".\r
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\n" ); document.write( "\n" ); document.write( "Now multiply the first coefficient \"1\" by the last term \"8\" to get \"%281%29%288%29=8\".\r
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\n" ); document.write( "\n" ); document.write( "Now the question is: what two whole numbers multiply to \"8\" (the previous product) and add to the second coefficient \"6\"?\r
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\n" ); document.write( "\n" ); document.write( "To find these two numbers, we need to list all of the factors of \"8\" (the previous product).\r
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\n" ); document.write( "\n" ); document.write( "Factors of \"8\":\r
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\n" ); document.write( "\n" ); document.write( "Note: list the negative of each factor. This will allow us to find all possible combinations.\r
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\n" ); document.write( "\n" ); document.write( "These factors pair up and multiply to \"8\".\r
\n" ); document.write( "\n" ); document.write( "1*8 = 8
\n" ); document.write( "2*4 = 8
\n" ); document.write( "(-1)*(-8) = 8
\n" ); document.write( "(-2)*(-4) = 8\r
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\n" ); document.write( "\n" ); document.write( "Now let's add up each pair of factors to see if one pair adds to the middle coefficient \"6\":\r
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First NumberSecond NumberSum
181+8=9
242+4=6
-1-8-1+(-8)=-9
-2-4-2+(-4)=-6
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\n" ); document.write( "\n" ); document.write( "From the table, we can see that the two numbers \"2\" and \"4\" add to \"6\" (the middle coefficient).\r
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\n" ); document.write( "\n" ); document.write( "So the two numbers \"2\" and \"4\" both multiply to \"8\" and add to \"6\"\r
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\n" ); document.write( "\n" ); document.write( "Now replace the middle term \"6x\" with \"2x%2B4x\". Remember, \"2\" and \"4\" add to \"6\". So this shows us that \"2x%2B4x=6x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2Bhighlight%282x%2B4x%29%2B8\" Replace the second term \"6x\" with \"2x%2B4x\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E2%2B2x%29%2B%284x%2B8%29\" Group the terms into two pairs.\r
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\n" ); document.write( "\n" ); document.write( "\"x%28x%2B2%29%2B%284x%2B8%29\" Factor out the GCF \"x\" from the first group.\r
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\n" ); document.write( "\n" ); document.write( "\"x%28x%2B2%29%2B4%28x%2B2%29\" Factor out \"4\" from the second group. The goal of this step is to make the terms in the second parenthesis equal to the terms in the first parenthesis.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B4%29%28x%2B2%29\" Combine like terms. Or factor out the common term \"x%2B2\"\r
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\n" ); document.write( "\n" ); document.write( "So \"x%5E2%2B6x%2B8\" factors to \"%28x%2B4%29%28x%2B2%29\".\r
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\n" ); document.write( "\n" ); document.write( "Since \"x%5E2%2B6x%2B8=%28x%2B4%29%28x%2B2%29\" and \"x%5E2%2B6x%2B8=0\", this means that \"%28x%2B4%29%28x%2B2%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "So we've gone from \"x%5E2%2B6x%2B8=0\" to \"%28x%2B4%29%28x%2B2%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "Now remember that if AB = 0 (A times B equals zero), then either A=0, B=0 or both are equal to zero. This is the zero product property.\r
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\n" ); document.write( "\n" ); document.write( "So use the zero product property to break \"%28x%2B4%29%28x%2B2%29=0\" down into the following equations shown below:\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B4=0\" or \"x%2B2=0\"\r
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\n" ); document.write( "\n" ); document.write( "Now solve each equation to get \r
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\n" ); document.write( "\n" ); document.write( "\"x=-4\" or \"x=-2\"\r
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\n" ); document.write( "\n" ); document.write( "So the two solutions are \"x=-4\" or \"x=-2\"\r
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\n" ); document.write( "\n" ); document.write( "Method # 2: Quadratic Formula\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B6x%2B8=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"x%5E2%2B6x%2B8\" is in the form of \"Ax%5E2%2BBx%2BC\" where \"A=1\", \"B=6\", and \"C=8\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for \"x\":\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-B+%2B-+sqrt%28+B%5E2-4AC+%29%29%2F%282A%29\" Start with the quadratic formula\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-%286%29+%2B-+sqrt%28+%286%29%5E2-4%281%29%288%29+%29%29%2F%282%281%29%29\" Plug in \"A=1\", \"B=6\", and \"C=8\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-6+%2B-+sqrt%28+36-4%281%29%288%29+%29%29%2F%282%281%29%29\" Square \"6\" to get \"36\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-6+%2B-+sqrt%28+36-32+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%288%29\" to get \"32\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-6+%2B-+sqrt%28+4+%29%29%2F%282%281%29%29\" Subtract \"32\" from \"36\" to get \"4\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-6+%2B-+sqrt%28+4+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-6+%2B-+2%29%2F%282%29\" Take the square root of \"4\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-6+%2B+2%29%2F%282%29\" or \"x+=+%28-6+-+2%29%2F%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4%29%2F%282%29\" or \"x+=++%28-8%29%2F%282%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+-2\" or \"x+=+-4\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x+=+-2\" or \"x+=+-4\" \r
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\n" ); document.write( "Note: the order of the solutions does not matter.
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