document.write( "Question 4743: solve each equation for x using factoring. please show work.\r
\n" ); document.write( "\n" ); document.write( "x2-4x+1=13\r
\n" ); document.write( "\n" ); document.write( "x2+2x+48=15x\r
\n" ); document.write( "\n" ); document.write( "5x2+7=52\r
\n" ); document.write( "\n" ); document.write( "3x2=4-11x\r
\n" ); document.write( "\n" ); document.write( "2x3+4x=6x2\r
\n" ); document.write( "\n" ); document.write( "2x2-4=7x
\n" ); document.write( "

Algebra.Com's Answer #2989 by guapa(62)\"\" \"About 
You can put this solution on YOUR website!
1)x²-4x+1=13 In order to factor the right side has to be 0. So, we substract 13 from both sides.
\n" ); document.write( "x²-4x+1-13=13-13
\n" ); document.write( "x²-4x-12=0 Now we need 2 numbers whose sum is -4 and whose factor is -12. To find them we express 12 in its prime factors. 2*2*3 By grouping these factors in various ways we find that 6(2*3), 2(2)and 2*6=12 Since we need -12 one of these factors has to be negative. -6*2=-12 and -6+2=-4 Now we can express the middle terms as -6x+2x. Therefore, we can complete the factoring as follows:
\n" ); document.write( "x²-6x+2x-12=0 Factor by grouping(x from first two terms and 2 from last two terms)
\n" ); document.write( "x(x-6)+2(x-6)=0 Factor common binominal factor of (x-6) from both terms.
\n" ); document.write( "(x-6)(x+2)=0 For all real numbers: ab=0 if and only if a=0 or b=0
\n" ); document.write( "Let's use this technique:
\n" ); document.write( "a=0, (x-6)=0 , x=6 ->(6-6)=0
\n" ); document.write( "b=0, (x+2)=0 , x=-2 ->(-2+2)=0
\n" ); document.write( "The solution set is (-2,6)
\n" ); document.write( "Check:
\n" ); document.write( "6²-4(6)+1=13
\n" ); document.write( "36-24+1=13
\n" ); document.write( "13=13
\n" ); document.write( "(-2)²-4(-2)+1=13
\n" ); document.write( "4-(-8)+1=13
\n" ); document.write( "4+8+1=13
\n" ); document.write( "13=13
\n" ); document.write( "Use this process for all following problems\r
\n" ); document.write( "\n" ); document.write( "2)x²+2x+48=15x
\n" ); document.write( "x²-13x+48=0
\n" ); document.write( "48 expressed in its prime factors: 2*2*2*2*3. The solution to this problem is not factorable since there are no two numbers whose sum is -13 and whose product is 48.\r
\n" ); document.write( "\n" ); document.write( "3)5x²+7=52
\n" ); document.write( "5x²+7-52=52-52
\n" ); document.write( "5x²-45=0 Divide both sides by 5
\n" ); document.write( "(5x²-45)/5=0/5
\n" ); document.write( "x²-9=0 The difference of two squares {a²-b²= (a-b)(a+b)}
\n" ); document.write( "(x-3)(x+3)=0
\n" ); document.write( "x-3=0, x=3
\n" ); document.write( "x+3=0, x=-3 Solution set is (-3,3)\r
\n" ); document.write( "\n" ); document.write( "4)3x²=4-11x
\n" ); document.write( "3x²+11x-4=0 (2 numbers whose sum is 11 and whose product is -12(3*-4)
\n" ); document.write( "3x²+12x-x-4=0
\n" ); document.write( "3x(x+4)-1(x+4)=0
\n" ); document.write( "(x+4)(3x-1)=0
\n" ); document.write( "x+4=0, x=-4
\n" ); document.write( "3x-1=0, x= 1/3 Solution set is (-4,1/3)\r
\n" ); document.write( "\n" ); document.write( "5)2x³+4x=6x²
\n" ); document.write( "2x³-6x²+4x=0 Divide both sides by 2
\n" ); document.write( "x³-3x²+2x=0 Factor out x
\n" ); document.write( "x(x²-3x+2)=0
\n" ); document.write( "x(x²-2x-x+2)=0
\n" ); document.write( "x(x-2)(x-1)=0
\n" ); document.write( "x-2=0, x=2
\n" ); document.write( "x-1=0, x=1 Solution set is (0,1,2)\r
\n" ); document.write( "\n" ); document.write( "6)2x²-4=7x
\n" ); document.write( "2x²-7x-4=0
\n" ); document.write( "2x²-8x+x-4=0
\n" ); document.write( "2x(x-4)+1(x-4)=0
\n" ); document.write( "(x-4)(2x+1)=0
\n" ); document.write( "x-4=0, x=4
\n" ); document.write( "2x+1=0, x= -(1/2) Solution set is (-1/2,4)
\n" ); document.write( "I hope this helps\r
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