document.write( "Question 1074078: If (3-x), 6, (7-5x) are consecutive terms of a geometric progression with constant ratio r>0 find x and constant ratio \n" ); document.write( "
Algebra.Com's Answer #688884 by htmentor(1343)![]() ![]() You can put this solution on YOUR website! We can write two equations for the common ratio: \n" ); document.write( "r = 6/(3-x) [1] \n" ); document.write( "r = (7-5x)/6 [2] \n" ); document.write( "We have two equations in two unknowns. Let's solve for x first. \n" ); document.write( "6/(3-x) = (7-5x)/6 -> 36 = 21 - 22x + 5x^2 -> 5x^2 - 22x - 15 = 0 \n" ); document.write( "This can be factored as (5x+3)(x-5) = 0. The two solutions are x = -3/5, x = 5. \n" ); document.write( "But, x=5 gives r<0, so we choose the 1st solution, x = -3/5. \n" ); document.write( "Substitute in [1] to get the value for r: \n" ); document.write( "r = 6/(3--3/5) = 6/(18/5) = 5/3. \n" ); document.write( "Ans: r = 5/3, x = -3/5 \n" ); document.write( " \n" ); document.write( " |