"What is the area? You should be able to solve this"
08-08-2018, 04:44 PM (This post was last modified: 08-08-2018 04:45 PM by Voldemar.)
Post: #20
 Voldemar Member Posts: 222 Joined: Mar 2014
RE: "What is the area? You should be able to solve this"
Area of quadrangle by coordinates:
S = ((x1*y2 - y1*x2) + (x2*y3 - y2*x3) + (x3*y4 - y2*x4) + (x4*y1 - y4*x1))/2

We have four quadrangles:
16 = ((0*y - a*x) + (x*2a - y*a) + (a*2a - 2a*0) + (0*a - 2a*0))/2
20 = ((0*0 - 0*a) + (a*y - 0*x) + (x*a - y*0) + (0*0 - a*0))/2
32 = ((a*0 - 0*2a) + (2a*a - 0*2a) + (2a*y - a*x) + (x*0 - y*a))/2
S = ((x*a - y*2a) + (2a*2a - a*2a) + (2a*2a - 2a*a) + (a*y - 2a*x))/2
After simplification:
16 = (a*x - a*y +2a^2)/2
20 = (a*x + a*y)/2
32 = (a*y - a*x + 2a^2)/2
S = (-a*x - a*y + 4a^2)/2
Take Prime:

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 Messages In This Thread "What is the area? You should be able to solve this" - Gerson W. Barbosa - 08-06-2018, 06:53 PM RE: "What is the area? You should be able to solve this" - Albert Chan - 08-06-2018, 09:12 PM RE: "What is the area? You should be able to solve this" - Albert Chan - 08-07-2018, 02:41 AM RE: "What is the area? You should be able to solve this" - Jim Horn - 08-06-2018, 09:14 PM RE: "What is the area? You should be able to solve this" - ijabbott - 08-06-2018, 09:16 PM RE: "What is the area? You should be able to solve this" - Albert Chan - 08-06-2018, 10:08 PM RE: "What is the area? You should be able to solve this" - Albert Chan - 08-06-2018, 10:52 PM RE: "What is the area? You should be able to solve this" - Robert VM - 08-07-2018, 07:16 PM RE: "What is the area? You should be able to solve this" - Gerson W. Barbosa - 08-07-2018, 12:12 AM RE: "What is the area? You should be able to solve this" - Thomas Klemm - 08-07-2018, 12:41 AM RE: "What is the area? You should be able to solve this" - Albert Chan - 08-07-2018, 12:57 AM RE: "What is the area? You should be able to solve this" - Gerson W. Barbosa - 08-07-2018, 01:53 AM RE: "What is the area? You should be able to solve this" - Gerson W. Barbosa - 08-07-2018, 01:11 AM RE: "What is the area? You should be able to solve this" - Diego Diaz - 08-07-2018, 02:10 AM RE: "What is the area? You should be able to solve this" - Pekis - 08-07-2018, 08:59 AM RE: "What is the area? You should be able to solve this" - Albert Chan - 08-07-2018, 02:20 PM RE: "What is the area? You should be able to solve this" - Robert VM - 08-07-2018, 07:24 PM RE: "What is the area? You should be able to solve this" - tpugsley - 08-08-2018, 01:11 PM RE: "What is the area? You should be able to solve this" - Albert Chan - 08-08-2018, 01:51 PM RE: "What is the area? You should be able to solve this" - Voldemar - 08-08-2018 04:44 PM RE: "What is the area? You should be able to solve this" - roadrunner - 08-08-2018, 05:03 PM

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