What are the three most popular equations in the world?
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x+y........e=mc2..........2+2
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The trick here is to find three equations where three of the variables are expressed functions of another variable. \nSo for example we could express x, y and w functions of z\nIf you add the first equation to the third and substract the second, you'll find: y= -3-z. We'll call this new equation A\nIf you add the second and the fourth equation and replace y by its value found in (A), you'll have: w= 7/4 + 1/4 z, which we'll call (B)\nNow take the first equation and replace w and y by their value from (A) and (B): \nx= -17/2 -7/2 z, this is the equation (C).\nNow that you have your three equations A,B and C you can substitute them in one of the four initial equations, for example the third one. You'll find:\nz=1\ny= -4\nw=2\nx= -12\nThis is not the entire solution (you have to detail how to get to A, B and C) but you should be able to do it (I don't want to be the only one working here!)
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Use cubic equation \ny=ax3+bx2+cx+d\n\nSince you have four points data you can get four linear equations with four variables which is very easy to solve, get variables (a,b,c,d) and plug the values to cross check and see u will get answer. Use guass jordan or elimination method.
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1) 21.69\n2) 14.10\n3) 7.59
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Well, number one would be:\n\nCost=0.03X^2 +1.15X + 1.37\n\n(An approximation)
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There is a mathmatical equation for the Eiffel tower...this way you have a visual that everyone knows and the info is on-line
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Take y on the other side\n\ny^2 dy/dx + y^3 = e^(x)\nMultiply by 3\n\n3 y^2 dy/dx + 3 y^3 = 3 e^(x)\n\nFirst term is d/dx (y^3)\nHence put z = y^3 and teh equation becomes\ndz/dx + 3z = 3 e^(x)\n\nNow this is in standard form\nMultiply throughout by e^(3x)\n\ne^(3x) dz/dx+ 3 e^(3x) z = 3 e^(4x)\nLHS can be re-written as\n\nd/dx { e^(3x)* z) = 3 e^(4x)\nIntegrate both sides\ne(3x)*z = 3 e^(4x)/4 +C\n\nz = 3/4 e^(4x)*e^(-3x) + C e^(-3x)\n\nSubstitute back for z=y^3
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is there more than one answer?  it seems like it since with the information you get, you can only make two equations, but with three variables.  anyways, here's one possible answer (i must say it wasn't much of a brain teaser):\n\n56 mice, 41 cats, 3 dogs\n\n[[edit]]\n\nah yes, the guy below me got it.  never realized to make those two equations equal :)
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[(y^2 + y )/(y+ 2)] / [(y^2 + 3y)/(y^2-4)]\n= [(y^2 + y )/(y+ 2)] times (y^2-4)/(y^2+3y)\nFactor everything\ny^2 + y = y(y+1)\ny^2 + 3y = y(y+3)\ny^2 - 4 = (y+2)(y-2)\nCancel anything on the top with anything on the bottom\nAnswer: (y+1)(y-2)/(y+3)
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Brackets, Orders, Division, Multiplication, Addition, Subtraction.\nIn some countries its BEDMAS, where E is exponents.
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1. second\n2. first\n3. 4100\n4. mary
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Ummm...\nThe equation of algebra, eh?\nWhat on earth are teachers teaching kids these days?!
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Atmosphere\nPascal\nBar\nlbs/cm^2
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First, you use the point slope formula:\ny-y1=m(x-x1)\n\ny-2=3(x-0)\ny-2=3x\ny=3x+2\n\nStandard form:\nAx+By=C\n\nSubtract 3x on both sides:\n-3x+y=2\nThat's your standard form!
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http://en.wikipedia.org/wiki/Cubic_equation
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http://en.wikipedia.org/wiki/Linear_equations\n\nhttp://en.wikipedia.org/wiki/Math
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can you give examples (such as the witches equation)