- Thread starter
- #1

#### Albert

##### Well-known member

- Jan 25, 2013

- 1,225

1,2,3,4 are four side length of a trapezoid,please find the area of

this trapezoid

this trapezoid

- Thread starter Albert
- Start date

- Thread starter
- #1

- Jan 25, 2013

- 1,225

1,2,3,4 are four side length of a trapezoid,please find the area of

this trapezoid

this trapezoid

- Thread starter
- #3

- Jan 25, 2013

- 1,225

yes, your answer is correct =$\dfrac {10\sqrt 2}{3}$

can you show your detailed solution please ?

We don't do homework here

OK; of the 6 possibilities, only 1:4 is possible as parallels;

can be easily shown using triangle inequality. Good nuff?

Code:

```
A 1 B
2 3
D 3-e F 1 E e C
```

triangleADF: h^2 = 2^2 - (3 - e)^2

triangleBCE: h^2 = 3^2 - e^2

SO:

2^2 - (3 - e)^2 = 3^2 - e^2

solve: e = 7/3

so DF = 2/3 and h = (4/3)SQRT(2)

Leads to area = 5*SQRT(32/9) / 2

which may be simplified to 10SQRT(2) / 3.

- Thread starter
- #5

- Jan 25, 2013

- 1,225

This is not my homework ,at first you must decide how to plot this trapezoid(this part may be a challenge)

here is my solution :

$h^2=9-x^2---(1)$

$h^2=4-(3-x)^2---(2)$

from (1)(2) we get $x=\dfrac {7}{3},\,\, and ,\,\, h=\dfrac {4\sqrt 2}{3}$

$\therefore area=2.5h=\dfrac {10\sqrt 2}{3}$

I know that, Albert; I was making a jokeThis is not my homework...

I see no difference between your solution and mine.