document.write( "Question 135087: Hello,I was wondering if anyone could help me solve this equation? I'm having trouble with it.
\n" ); document.write( "x^2-3x=18 the directions are to solve the equation.\r
\n" ); document.write( "\n" ); document.write( "Thank you,
\n" ); document.write( "Mrs. Gibson
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Algebra.Com's Answer #98926 by algebrapro18(249)\"\" \"About 
You can put this solution on YOUR website!
Well in order to solve a quadratic equation we first must have it in standard form. Standard form is ax^2+bx+c = 0 where a, b, and c are numbers.
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\n" ); document.write( "\n" ); document.write( "so putting the function into standard form you get:
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\n" ); document.write( "\n" ); document.write( "x^2-3x=18
\n" ); document.write( "x^2-3x-18=0
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\n" ); document.write( "\n" ); document.write( "now we need to factor. The steps to factoring are:
\n" ); document.write( "1) Multiply a times c
\n" ); document.write( "2) See what factors of the number found in step one add to the b value
\n" ); document.write( "3) break the function into a product of its factors
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\n" ); document.write( "\n" ); document.write( "In this example a = 1, b = -3, and c = -18. So a*c = -18. So we need to find the factors of -18 that add to -3. Well the factors of 18 are:
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\n" ); document.write( "\n" ); document.write( "1,-18
\n" ); document.write( "2,-9
\n" ); document.write( "3,-6
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\n" ); document.write( "\n" ); document.write( "well -6+3 = -3 so those are the factors we wanted.
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\n" ); document.write( "\n" ); document.write( "So we now know that x^2-3x-18 can be written as (x-6)(x+3). This is now in factored form.
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\n" ); document.write( "\n" ); document.write( "Now we use the zero product property that states that you can set each one of those factors equal to zero and solve for x.
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\n" ); document.write( "\n" ); document.write( "x-6 = 0
\n" ); document.write( "x = 6
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\n" ); document.write( "\n" ); document.write( "x+3 = 0
\n" ); document.write( "x = -3
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\n" ); document.write( "\n" ); document.write( "so now we know that the solutions to the given equation are x = -3 and x = 6.
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\n" ); document.write( "\n" ); document.write( "Now to check our solutions:
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\n" ); document.write( "\n" ); document.write( "x^2-3x-18 = 0
\n" ); document.write( "(6)^2-3(6)-18=0
\n" ); document.write( "36 - 18 - 18 = 0
\n" ); document.write( "36 - 36 = 0
\n" ); document.write( "0 = 0
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\n" ); document.write( "\n" ); document.write( "that solution checks out now lets check the other one
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\n" ); document.write( "\n" ); document.write( "x^2-3x-18 = 0
\n" ); document.write( "(-3)^2 - 3(-3) - 18 = 0
\n" ); document.write( "9 + 9 - 18 = 0
\n" ); document.write( "18 - 18 = 0
\n" ); document.write( "0 = 0
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\n" ); document.write( "\n" ); document.write( "that solution also check's out.
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