Question

I have to find the area

Answer 1

Your best choice is 11.55. 

5.5 · 4.2 equals 23.1. You don't need the 6.9.

You then need to do 23.1 ÷ 2 which is 11.55 m².

Hope this helps!

Answer 2

The formula for finding the area of a triangle is: base*height*1/2
So, if we use this information....
4.2*5.5*1/2=11.55
Area=11.55