factor 25u squared minus 81?
411840
x^2 - y^2 = (x+y)(x-y)\n\nso 25u^2-81= (5u+9)(5u-9)
395264
If that one choice, 81/4 means 8.25, then that is the answer
677061
i think this formula works.\nfactorial of A-4A\nso.using this formula the correct answer is 5012
805233
Can you factor the numerator?\n\nI guess not, but UMR math major ignores your denominator in the original problem.
898178
-25\n-5*(-3+8) = -5*(5) = -25
839180
it is radical 8\nrt8 or 2.828
700653
Yes you're correct - just plug in -2 for x to get: \n \n20 - -6 + 1 = 27
821366
2.7*10^-5\n7.041*10^5
757415
1) yes\n2) get rid of x factor, so -(x^3-1)/(x^2+1)\n3) You lost a negative, (2x+3)/(3-2x)\n4) Remove y factor: 7x/2y\n\nSteve
255444
jf rodrigues is correct to add 65. The others are putting in parentheses where none appear in the problem. They end up subtracting 65 instead of adding, and are getting answers that are too low by 130.\n\nThe wrong answers are obtained by people subtracting and even multiplying(!) 65 when they should be adding it.
927521
1/2bh\n1/2(8.5)(5.5)\n23.375
903769
You can cross-cancel, and then multiply ... at least I think that's what it's called. \n\nLet's say you have the problem 27/4 x 16/9. Looks somewhat large at first, but you can make it really simple. The 9 and 27 can be reduced, because 9 is a factor of both of those numbers. Take 9 out of each and you get 3/4 x 16/1. Then you can take 4 out of the 16 and the 4. You're left with the problem 3/1 x 4/1, which equals 12/1. That reduces to 12.\n\nA long-looking problem that can be easily simplified. Hope that helps.
779020
Just a number. Also, the answer is 3, not 37. You just have to substitute -1/3 where there is an x in the original.\n\nf(x) = 18x(squared) - 12x - 3\nf(-1/3) = 18 * (-1/3)^2 - 12 * ( -1/3) - 3\n                    18 * 1/9     + 4            - 3\n                             2 + 4 -3\n                                  3
142846
You get 2 factors that are (b plus or minus something) times (b plus or minus something). If the “sign” before the number at the end of the equation is negative, then you have one of the factors as (b plus something) times (b minus something). The two “somethings” multiplied equal 24. They could be 1x24, 2x12, 3x8, or 4x6. The “5b” in the middle shows you this: one of the missing numbers is 5 greater than the other. 3x8 works here. Since the sign of the “5b” in the middle is positive, the larger missing number is positive. Your answer is:\n(b+8)(b-3)\n\nCheck: first: b*b=b^2. b*8=8b. b*-3=-3b. 8*-3=-24.\nAdd these up and you get b^2 +8b –3b –24.\nb^2 +5b –24
146354
x square-12x-85\nI think?
131300
-8x+2=26\nsubtract 2 from both sides.\n-8x=24\ndivide both sides by -8\nx=-3
1150392
No problem, i just finished a calc3 course in college.\n\nYour problem is the same as 125 * (6x^2 + 5x + 7)^(-1/3)\nYou have to use the chain rule so you get\n125 * (-1/3) * (12x + 5) * (6x^2 +5x + 7)^(-4/3)\n\nthen you can simplify how you like from there