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ttokoro
21-Topaz I
Feb 26, 2024 12:12 PM UTC
Solved

Puzzle-35. Find the Length DE. ABCD is rectangular. 5 areas are same sizes. AB=13 cm.

Not a question of mathcad but Mathcad can solve this.

Find the Length DE.

ABCD is rectangular. 5 areas are same sizes. AB=13 cm.

 

ttokoro_6-1708949375898.png

 

terryhendicott
21-Topaz II
Feb 26, 2024 2:11 PM UTC

Hi

See Enclosed

8 replies

Werner_E
25-Diamond I
Feb 26, 2024 1:52 PM UTC

Its not difficult to get DE=6, but Mathcad or Prime were of no help here (or rather: weren't needed).

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terryhendicott
21-Topaz II
Feb 26, 2024 2:11 PM UTC
Werner_E
25-Diamond I
Feb 26, 2024 2:51 PM UTC

To be on the safe side we would need a symbolical solution, but trying to evaluate  the solve block symbolically fails.

Reason is that yD actually is irrelevant and yD could be set to any constant value and need not to be solved for.

So when we solve for four unknowns, we also only need four equations - one of the area equations is redundant anyway - if four of the five trinagles have an area of 1/5 of the total area, I would be surprised if the fifth triangle would have another area.
Now symbolical evaluation works OK

Werner_E_1-1708959439581.png

 

 

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23-Emerald I
Mar 2, 2024 8:06 AM UTC

Attached. prime 4 express

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ttokoro
ttokoro21-Topaz IAuthor
21-Topaz I
Mar 2, 2024 10:38 AM UTC

Hights of triangle DEG and ECH are not same but areas are same.

image.png

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t.t.