document.write( "Question 1108950: find three consecutive even integers such that the product of the first and third is 20 less than 10 times the second \n" ); document.write( "
Algebra.Com's Answer #723965 by addingup(3677)![]() ![]() You can put this solution on YOUR website! n-2 * n+2 = 10(n)-20 \n" ); document.write( "n-2 * n+2 = 10n - 20 \n" ); document.write( "n(n+2) + (-2)(n+2) = 10n - 20 \n" ); document.write( "n^2 + 2n + (-2)(n + 2) = 10n - 20 \n" ); document.write( "n^2 + 2n + ((-2)n +(-2) * 2) = 10n - 20 \n" ); document.write( "n^2 + 2n + (-2)n - 4 = 10n - 20 \n" ); document.write( "n^2 - 4 = 10n - 20 \n" ); document.write( "n^2 - 4 - (10n - 20) = 0 \n" ); document.write( "n^2 - 4 + ((-1) * 10n + (-20)(-1)) = 0 \n" ); document.write( "n^2 - 4 + ((-10)n + (-20)(-1) = 0 \n" ); document.write( "n^2 - 4 + (-10)n + 20 = 0 \n" ); document.write( "n^2 + 16 + (-10)n = 0 \n" ); document.write( "n^2 + (-10)n + 16 = 0 \n" ); document.write( "n^2 + (-10)n = -16 \n" ); document.write( "The coefficient of n is -10. Divide by 2 and square (-10/2 = -5; -5^2 = 25), then add result to both sides of the equation: \n" ); document.write( "n^2 + (-10)n + 25 = 9 \n" ); document.write( "now we have the equation in the form x^2 + bx + c, a perfect square we can factor: \n" ); document.write( "(n-5)^2 = 9 \n" ); document.write( "Take the square root of both sides: \n" ); document.write( "n-5 = 3 \n" ); document.write( "n = 8 \n" ); document.write( "your numbers are: \n" ); document.write( "n - 2, n, n + 2 \n" ); document.write( "= 8 - 2, 8, 8 + 2 \n" ); document.write( "= 6, 8, 10 Three even consecutive integers \n" ); document.write( "the product of the first and third is 20 less than 10 times the second: \n" ); document.write( "6(10) = 10(8) - 20 \n" ); document.write( "60 = 80 - 20 Correct\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |