Question

10. In the figure above AD = 4, AB = 3 and CD = 9. What is the area of triangle AEC ?

A. 18
B. 13.5
C. 9
D. 4.5
E. 3

Answer 1

can you draw the picture first

Answer 2

The two triangles AEB and DEC are similar than
\[
\frac {CD}{AB}=\frac {ED}{AE}= \frac 9 3\\
ED= 3 AE\\and\\
AD= 4\\then\\
AE=1\\
ED=3
\]
Can you finish it now?

Answer 3

So if you now, label the picture with the given, do you see any useful info?

Answer 4

Area ACD = 9x4/2= 18
Area AED= 3x 9/2= 27/2=13.5
Area AEC= 18-13.5= 4.5