document.write( "Question 251564: hi im a 13 year old boy in 8th grade in algerbra 1 honors class. im really stumped on these questions and need some help please. Please help me and thank you very much. merry early christmas!!
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document.write( "(1)The sum of the reciprocals of two consecutive odd integers is 8/15. find the number.
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document.write( "(2)The sum of the reciprocals of two consecutive even integers is 11/60. find the integers.
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document.write( "(3) the sum of two numbers is 10 and the sum of there reciprocals is 5/12. find the numbers. \n" );
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Algebra.Com's Answer #183266 by stanbon(75887) ![]() You can put this solution on YOUR website! (1)The sum of the reciprocals of two consecutive odd integers is 8/15. find the number. \n" ); document.write( "Odd numbers are always one more than or one less than an even number. \n" ); document.write( "Symbols for an odd number are 2x-1 or 2x+1 \n" ); document.write( "------------------- \n" ); document.write( "Your problem: \n" ); document.write( "1st odd: 2x-1 \n" ); document.write( "Next consecutive odd: 2x+1 \n" ); document.write( "------------------------------- \n" ); document.write( "Equation: \n" ); document.write( "1/(2x-1) + 1/(2x+1) = 8/15 \n" ); document.write( "--- \n" ); document.write( "Multiply thru by 15(2x-1)(2x+1): \n" ); document.write( "15(2x+1) + 15(2x-1) = 8(2x+1)(2x-1) \n" ); document.write( "30x+15 + 30x-15 = 8(4x^2-1) \n" ); document.write( "60x = 32x^2-8 \n" ); document.write( "32x^2-60x-8 = 0 \n" ); document.write( "8x^2-15x-2 = 0 \n" ); document.write( "8x^2-16x+x-2 = 0 \n" ); document.write( "8x(x-2)+(x-2) = 0 \n" ); document.write( "(x-2)(8x+1) = 0 \n" ); document.write( "Positive solution: \n" ); document.write( "x = 2 \n" ); document.write( "---- \n" ); document.write( "1st odd: 2x-1 = 3 \n" ); document.write( "2nd odd: 2x+1 = 5 \n" ); document.write( "======================== \n" ); document.write( "Checking \n" ); document.write( "1/3 + 1/5 = 8/15 \n" ); document.write( "Multiply thru by 15: \n" ); document.write( "5 + 3 = 8 \n" ); document.write( "8 = 8 \n" ); document.write( "=================\r \n" ); document.write( "\n" ); document.write( "(2)The sum of the reciprocals of two consecutive even integers is 11/60. find the integers. \n" ); document.write( "Follow the same procedure as in #1 but use the followin symbols \n" ); document.write( "for consecutive even numbers. \n" ); document.write( "1st: 2x \n" ); document.write( "2nd: 2x+2 \n" ); document.write( "=============================== \n" ); document.write( "(3) the sum of two numbers is 10 and the sum of their reciprocals is 5/12. \n" ); document.write( "Find the numbers. \n" ); document.write( "---- \n" ); document.write( "Equations: \n" ); document.write( "x + y = 10 \n" ); document.write( "1/x + 1/y = 5/12 \n" ); document.write( "----------------------- \n" ); document.write( "Rearrange the equations: \n" ); document.write( "x = 10-y \n" ); document.write( "12y + 12x = 5xy \n" ); document.write( "------------------- \n" ); document.write( "Substitute for \"x\" and solve for \"y\": \n" ); document.write( "12y + 12(10-y) = 5(10-y)y \n" ); document.write( "12y + 120 - 12y = 50y - 5y^2 \n" ); document.write( "5y^2 -50y+120 = 0 \n" ); document.write( "y^2 - 10y + 24 = 0 \n" ); document.write( "(y-6)(y-4) = 0 \n" ); document.write( "y = 6 or y = 4 \n" ); document.write( "--- \n" ); document.write( "Substitute into x 10-y \n" ); document.write( "If y = 6, x= 4 \n" ); document.write( "If y = 4, y = 6 \n" ); document.write( "====================== \n" ); document.write( "Checking: \n" ); document.write( "x+y = 10 \n" ); document.write( "4+6 = 10 \n" ); document.write( "--------- \n" ); document.write( "1/4 + 1/6 = 5/12 \n" ); document.write( "Multiply thru by 12 to get: \n" ); document.write( "3+2 = 5 \n" ); document.write( "=================== \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( " |