## Asivrs 3 years ago An engineer wanted to approximate the width, in feet of a river. she placed markers at point A and point B to represent the average width of the river. She also placed 3 other markers along the riverbank and measured the distances shown in the diagram below. Based on this diagram, what was the width of the river, in feet, from point A to point B?

1. Asivrs

|dw:1337276808827:dw|

2. atlas

Use similarity of triangles

3. atlas

The two triangles that u see are similar and hence their corresponding sides will have the same ration

4. Asivrs

so..i should put 62 over 93 and 49 over X?

5. Asivrs

find the ratio after that then... times it by 2?

6. atlas

Label the two triangles and see which angles are equal................The sides corresponding to equal angles are proportional|dw:1337277341870:dw| here AB:AC = BE:CD

7. atlas

You do not know AB............So let it be x

8. Asivrs

but you dont know AD either.. right?

9. atlas

U do not need AD................The equation AB:AC = BE:CD can be written as x/(x+49)= 62/93 Solve for x (Remember x = AB)

10. atlas

|dw:1337277608429:dw|

11. Asivrs

$\left[\begin{matrix}x & 62\\ x+49 & 93\end{matrix}\right]$

12. Asivrs

like okay.. x + 49 = AC,, so... ugh sorry i dont get math easily

13. Asivrs

is there like a formula you can give me to help me out? i know if i see what i need to do i'll understand.