document.write( "Question 203173: Solving Quadratics\r
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document.write( "2x2 - 4x + 1 = 0
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document.write( " 8. 3x2 + 2x = 7
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document.write( " 9. x2 + 8x + 9 = -7
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Algebra.Com's Answer #153288 by jejess(7)![]() ![]() ![]() You can put this solution on YOUR website! This is all about factoring \n" ); document.write( " for the first one we have 2x^2 -4x +1 =0 \n" ); document.write( " You need to find two number that multiply 2 but add to negative 4 \n" ); document.write( "-2, -2 \r \n" ); document.write( "\n" ); document.write( "now the question will read like this \n" ); document.write( "2x^2-2x-2x+1=0 \n" ); document.write( "To factor this one we group the first two terms together and the last two terms together. \n" ); document.write( "(2x^2-2x)(-2x+1)=0 \n" ); document.write( "Now we factor out what we can from the barkets \n" ); document.write( "In the first one (2x^2-2x) What is common about the two terms? 2 and x \n" ); document.write( "so we remove them \n" ); document.write( "2x(x-1) \n" ); document.write( "now do the same for the second set of barkets (-2x+1) \n" ); document.write( "-1 is common \n" ); document.write( "-(2x-1) \n" ); document.write( "Now the 2x-1 is common so we rewrite the question as this \n" ); document.write( "(2x-1)(x-1)=0 \n" ); document.write( "Solve for x by splitting the barkets up \n" ); document.write( "2x-1 = 0 OR x-1=0 \n" ); document.write( "slove by rearranging \n" ); document.write( "2x-1=0 or x-1=0 \n" ); document.write( "2x=1 x=1 \n" ); document.write( "x=1/2\r \n" ); document.write( "\n" ); document.write( "If you do not understand factoring and rearraging please say so in next question.\r \n" ); document.write( "\n" ); document.write( "I will answer the third one and you can try the second your own if you don't understand it please re-post with where you seem to go wrong. ie; factoring.\r \n" ); document.write( "\n" ); document.write( "The next one is a little tricky because the question is equal to something (-7) \n" ); document.write( "We must re-write the question then to make it equal zero in order to factor it. \n" ); document.write( "x^2+8x+9=-7 \n" ); document.write( "now will read this \n" ); document.write( "x^2+8x+9+7=0 REMEMBER when you move a number or term it changes signs a postive become a negative and vis versa. \n" ); document.write( "Collect like terms; so you add 9 and 7 to get 16 \n" ); document.write( "x^2+8x+16=0 \n" ); document.write( "Now you need to find two numbers that add to 8 but mult. to 16 \n" ); document.write( "4 and 4 and you split the middle term (8x) into these two numbers so the question reads like this now. \n" ); document.write( "x^2+4x+4x+16=0 \n" ); document.write( "(x^2 +4x)(4x+16)=0 \n" ); document.write( "x(x+4)4(x+4)=0 \n" ); document.write( "(x+4)(x+4)=0 \n" ); document.write( "or (x+4)^2 \n" ); document.write( "x must be = to -4 \n" ); document.write( "x+4=0 \n" ); document.write( "x=-4 \n" ); document.write( " \n" ); document.write( " |