Respuesta :

DEF= 6 ft^2

A= 1/2*b*h

Plug in what you know.

6= 1/2*4*h

Multiply like terms. 

6=2*h

Divide 2 on both sides. 

3=h

If the base of ABC= 12

12/4=3

3*3=9

A= 1/2*b*h
A= 1/2*12*9
A= 1/2*84
A= 42

The area of ABC is 42 ft^2

I hope this helps!
~kaikers