+0  
 
0
500
1
avatar

The diagram shows a triangle DEF inside a rectangle ABCD.

 

Show that that the area of triangle DEF is 11 cm^2.

 

 Mar 13, 2021
 #1
avatar
0

CD = sqrt((2√10)2 - 22) = 6 cm

 

[ABCD] = CD * AB = 30 cm2

 

[DEF] = [ABCD] - {1/2(4*5) + 1/2(2*3) + 1/2(2*6)} = 11 cm2

 Mar 15, 2021

3 Online Users

avatar
avatar