Re: NSolve output

*To*: mathgroup at smc.vnet.net*Subject*: [mg129433] Re: NSolve output*From*: Bob Hanlon <hanlonr357 at gmail.com>*Date*: Mon, 14 Jan 2013 00:00:50 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-newout@smc.vnet.net*Delivered-to*: mathgroup-newsend@smc.vnet.net*References*: <20130113025310.BFB386957@smc.vnet.net>

$Version "9.0 for Mac OS X x86 (64-bit) (November 20, 2012)" a = x z + 2 x y + 2 y z; v = x y z; a2 = a /. x -> 2 z; v2 = v /. x -> 2 z; NSolve[{a2 == 60, v2 == 40, x == 2 z, x > 0}, {x, y, z}] {{x -> 5.1156, y -> 3.05701, z -> 2.5578}, {x -> 7.46083, y -> 1.43719, z -> 3.73042}} Solve[{a2 == 60, v2 == 40, x == 2 z, x > 0}, {x, y, z}, Reals] // N {{x -> 5.1156, y -> 3.05701, z -> 2.5578}, {x -> 7.46083, y -> 1.43719, z -> 3.73042}} {Reduce[{a2 == 60, v2 == 40, x == 2 z, x > 0}, {x, y, z}, Backsubstitution -> True] // N // ToRules} {{x -> 5.1156, y -> 3.05701, z -> 2.5578}, {x -> 7.46083, y -> 1.43719, z -> 3.73042}} Bob Hanlon On Sat, Jan 12, 2013 at 9:53 PM, Berthold Hamburger <b-hamburger at artinso.com> wrote: > Hello, > > I want to solve two simple equations with NSOLVE to calculate the > dimensions of a rectangular box that is open on top. The length of the > box is twice the width and the volume and area of the box are > respectively 40 cubic feet and 60 square feet. > > I defined the area and volume: > a = xz + 2xy + 2yz > v = xyz > > then substituted x with 2z: > > a2 = a /. x->2z > v2 = v /. x->2z > > > > a2 = 6 y z + 2 z^2 > v2 = 2 y z^2 > > solved with NSolve: > step1 = NSolve[{a2 == 60, v2 == 40}, {y, z}, Reals] [[1,2]] //Column > > which returns the results > {y->3.05701,z->2.5578} > > I would like to get an output that returns values for all 3 variables > x,y,z as in > > {x->5.1156,y->3.05701,z->2.5578} > > but somehow cannot find a way to do it > > What would be the correct way for doing that? > > Regards > > Berthold Hamburger >

**References**:**NSolve output***From:*Berthold Hamburger <b-hamburger@artinso.com>