math help, no this isnt homework?
824758
Question 1 : 4^x - 2 * 5^(2x) < 10^x\n\nFactorise :\n2^(2x) - 2 * 5^(2x) < 2^x * 5^x\n\nDivide through by 2^(2x) :\n1 - 2 * (5/2)^(2x) < (5/2)^x\n\nLet y = (5/2)^x\n\nTherefore, 1 - 2y^2 < y\nor, 2y^2 + y - 1 > 0\nor, (y + 1)(2y - 1) > 0\nThus, y < -1 or y > 1/2\n\nThat is, (5/2)^x < - 1 or (5/2)^x > 1/2\n\nBut (5/2)^x is always > 0, so the only\nsolution occurs when (5/2)^x > 1/2.\n\nTake the reciprocal of both sides :\n(2/5)^x < 2\n\nTake logarithm of both sides :\nx(log2 - log5) < log2\n\nTherefore, x < log2 / (log2 - log5)\nor x < -0.7565 approximately.\n----------------------------------------------------------------------\nQuestion 2 : 7 * 3^(x + 1) - 5^(x + 2) = 3^(x + 4) - 5^(x + 3)\n\nDivide through by 3^(x + 1) :\n7 - 5 * (5/3)^(x + 1) = 27 - 25 * (5/3)^(x + 1)\n\nRearrange :\n20 * (5/3)^(x + 1) = 20\n\nTherefore, (5/3)^(x + 1) = 1 = (5/3)^0\nThus, x + 1 = 0, so, x = -1\n----------------------------------------------------------------------\nQuestion 3 : 6 * 9^(1/x) - 13 * 6^(1/x) + 6 * 4^(1/x) = 0\n\nFactorise for ease of viewing :\n6 * 3^(2/x) -13 * 2^(1/x) * 3^(1/x) + 6 * 2^(2/x) = 0\n\nDivide through by 6^(1/x), which equals 2^(1/x) * 3^(1/x) :\n6 * (3/2)^(1/x) - 13 + 6 * (2/3)^(1/x) = 0\n\nThe latter term, (2/3)^(1/x) = 1 / [ (3/2)^(1/x) ]\n\nSo now we have : 6 * (3/2)^(1/x) - 13 + 6 / [ (3/2)^(1/x) ] = 0\n\nLet y = (3/2)^(1/x)\n\nTherefore, 6y - 13 + 6 / y = 0\n\nMultiply through by y :\n6y^2 - 13y + 6 = 0\nor, (3y - 2)(2y - 3) = 0\nor, y = 2/3 or 3/2\n\nThat is, (3/2)^(1/x) = 2/3 or (3/2)^(1/x) = 3/2\n\nFirst, trying (3/2)^(1/x) = 2/3 = 1 / (3/2) = (3/2)^(-1)\nTherefore, 1 / x = -1, so x = -1.\n\nSecond, trying (3/2)^(1/x) = 3/2 = (3/2)^1\nTherefore, 1 / x = 1, so x = 1.\n\nSo there are 2 solutions, x = -1 or 1.
555590
Just multiply:\n(X/3)(3/4 x) -(x/3)(3/5) + (3/4)(3/4x) - (3/4)(3/5)\n\nand simplify from there
19107
x-0.15x+680 is not an equation, therefore it would not have a solution. But, it can be simplified to 0.85x+680.
974937
please complete the equation
677729
2/3 the number that is not a variable
1163900
http://education.yahoo.com/homework_help/math_help/
1007654
Is this your homework???  The answer is B, anyway.
426775
b = 2g - 10\ng = (b + 10)/2
891258
Try 1 ÷ 3\n\n1/3 = 0.33333.....\n\n~ ♥ ~
198853
Is this your homework, dude?
1135408
OH NOES THIS IS LIKE A MATH PROBLEM!!!! i can't handle any more variables :( sry.\n\n\nhahahaha.
859744
(x + 4y)(x - 4y)\nI answered 2 of your questions. Do the rest of the questions yourself.
14045
is this a homework assignment?
741999
whats the equation or formula u need help with?
113980
Use a calculator - numerator divided by denominator will give you the answer.
917052
16/24....it's really not that hard...you should be able to solve it on your own.\nps. you might want to simplify it down to 2/3.
1169800
work done 1.078 X 10^5\nheat is -0.292X10^5