+0  
 
-1
131
2
avatar+464 

This is probably my last question for the day

 

 Oct 15, 2018
 #1
avatar+98090 
+1

Triangles ADE, CD share the same base  (AC)

And triangles ADE and CDE  have the same altitudes...so....their bases are to each other as their areas

 

So  AD /DC  = 9/6   = 3/2

 

So...there are  5 equal parts of AC....and  AD  is 3 of them

So......AC / AD  =  5/3

 

Since triangles ADE and ABC are similar....the scale factor  of triangle  ABC to  triangle  ADE  is  (5/3)

 

So...  [ABC ] =  [scale factor of  ABC to ADE]^2  *  [ ADE ]  =

 

(5/3)^2 *  [ 9 ]  = 

 

25 / 9   *  [9]  =

 

25 units^2

 

 

cool cool cool

 Oct 15, 2018
 #2
avatar+464 
+1

Thank you Chris

 Oct 16, 2018

33 Online Users

avatar
avatar
avatar
avatar