"What is the area? You should be able to solve this"
08-06-2018, 10:52 PM (This post was last modified: 08-06-2018 10:55 PM by Albert Chan.)
Post: #6
 Albert Chan Senior Member Posts: 1,791 Joined: Jul 2018
RE: "What is the area? You should be able to solve this"
I have seen the geometric solution ! (no, i did not peek)

Since all points A=(0,2), B=(2,0), C=(4,2), D=(2,4) is the mid-point of square side,
Join them all, and it is still a square (no coordinates needed, but I can't draw with words)

Within this smaller square, the opposite triangles must sum to half of square.
(same base, 2 height sum to base, thus 2 triangles sum to base*base/2)

so, back to big square ...

opposite quadrilaterals also sum the same, to half of big square.

20 cm^2 + sx = 16 cm^2 + 32 cm^2

-> sx = 28 cm^2
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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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