The answer is the third one :)
Do you mean like this?
Y = -x - 4
Y = x
x = -x - 4
2x = -4
x = -2
Therefore y = -2
Answer:
45.8
Step-by-step explanation:
We need to find the surface area for this entire figure!
We can see that this is a pyramid here - we must find the area of the 3 triangles and the base triangle at the bottom.
The 3 triangles building up the pyramid are all equal to each other.
To find the area of a triangle, use 

Round to the nearest tenth: 45.75 -> 45.8