Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ π -¹ ² ³ °

You are not logged in.

- Topics: Active | Unanswered

Pages: **1**

**naturewild****Member**- Registered: 2005-12-04
- Posts: 30

This question is really easy but I'm weak in similar triangle.. I dont know how to do it.

In triangle ABC, D and E are in AB and AC respectively such that DE is parallel to BC, AD = 3, DB = 4, and triangle ADE = 81. Determine

1. triangle ABC

2. quadrilateral DBCE

Offline

**mikau****Member**- Registered: 2005-08-22
- Posts: 1,504

triangle ADE = 81 makes no sense. Do you mean ADE = 81 degrees or something?

A logarithm is just a misspelled algorithm.

Offline

**naturewild****Member**- Registered: 2005-12-04
- Posts: 30

oh those are the areas I mean.

Offline

**krassi_holmz****Real Member**- Registered: 2005-12-02
- Posts: 1,908

S[ade]:S[abc]=3:7

S[dbce]=S[abc]-S[ade]

So you can do it all alone.

IPBLE: Increasing Performance By Lowering Expectations.

Offline

**naturewild****Member**- Registered: 2005-12-04
- Posts: 30

I tried doing it that way. Let's say x = triangle ABC

ADE / ABC = 3 / 7

81/x = 3/7

x = 189

But the answer is 441

Offline

**John E. Franklin****Member**- Registered: 2005-08-29
- Posts: 3,585

Did you say that D is along AB and E is along BC?

If so, then DE is parallel to AC, not BC.

**igloo** **myrtilles** **fourmis**

Offline

**boyhuesd****Member**- Registered: 2006-03-02
- Posts: 1

o!

It very easy!

ec! ec!

Offline

Pages: **1**