document.write( "Question 559425: I need some help. It simply says find the solutions but I am not sure what method it is asking me to solve it with. I don't know if it means solve using the quadratic equation or if there is some other way I am suppose to be doing it. Please help! Thanks.\r
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document.write( "Find the solutions:\r
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document.write( "4) (m+3)^2 + 5(m+3) –14 = 0
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document.write( "5) (2x-1)^2 –4(2x-1) + 2 = 0\r
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Algebra.Com's Answer #363407 by Theo(13342)![]() ![]() You can put this solution on YOUR website! these are quadratic equations. \n" ); document.write( "instead of x, you have (m+3) \n" ); document.write( "instead of x, you have (2x-1) \n" ); document.write( "assign the expression inside the parentheses to a variable other than a variable that is being used in the parentheses and you'll see that more clearly. \n" ); document.write( "for your first problem: \n" ); document.write( "(m+3)^2 + 5(m+3) - 14 = 0 \n" ); document.write( "let x = m+3 \n" ); document.write( "your equation becomes: \n" ); document.write( "x^2 + 5x - 14 = 0 \n" ); document.write( "this factors to: \n" ); document.write( "(x+7) * (x-2) = 0 \n" ); document.write( "x = -7 or x = 2 \n" ); document.write( "for your second problem: \n" ); document.write( "(2x-1)^2 - 4(2x-1) + 2 = 0 \n" ); document.write( "let y = 2x-1 \n" ); document.write( "your equation becomes: \n" ); document.write( "y^2 - 4y + 2 = 0 \n" ); document.write( "this doesn't factor easily. \n" ); document.write( "use the quadratic formula on this. \n" ); document.write( "y = (-b +/- sqrt(b^2-4ac))/(2a). \n" ); document.write( "a = 1 \n" ); document.write( "b = -4 \n" ); document.write( "c = 2 \n" ); document.write( "----- \n" ); document.write( "-b = 4 \n" ); document.write( "sqrt(b^-4ac) = sqrt(8) \n" ); document.write( "2a = 2 \n" ); document.write( "----- \n" ); document.write( "y = (4 + sqrt(8))/2 = 3.414213562 \n" ); document.write( "y = (4 - sqrt(8))/2 = 0.585786438 \n" ); document.write( "------ \n" ); document.write( "since we set: \n" ); document.write( "y = 2x-1, then we get: \n" ); document.write( "2x-1 = 3.414213562 which results in: \n" ); document.write( "x = 2.207106781 \n" ); document.write( "and we get: \n" ); document.write( "2x-1 = .585786438 which results in: \n" ); document.write( "x = 0.792893219 \n" ); document.write( "there is no need to go back to the original equation of: \n" ); document.write( "(2x-1)^2 - 4(2x-1) + 2 = 0 because when we calculate 2x-1, we get y. \n" ); document.write( "since y is the value we used to solve the equation, we will get the same answer because: \n" ); document.write( "x = 2.207106781 times 2 minus 1 will equal 3.414213562 which is the value of y. \n" ); document.write( "similarly: \n" ); document.write( "x = 0.792893219 times 2 minus 1 will equal .585786438 which is the value of y. \n" ); document.write( "these 2 values of y are what we solved for originally.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |