It seems okay to me (if that what your asking) I don't know this subject very well ut the part your working on " I'm familiar with ?" Don't be surprised if I was wrong buuuuut it does look okay to me "(the answer)".
1. Area of triangle
1/2(10)(12)=60
There are two triangles, so multiply by 2
=120
2. Find area of the rectangles
This is an isosceles triangle, so the two rectangles are congruent
(2)(13)(3)=78
3. Find area of bottom rectangle
10(3)= 30
4. Add everything up
120+ 78 + 30= 228
Therefore the surface area of this prism is 228
I hope i helped :)
The y-intercept, in this case, represents when x is at 0, or when she just began observing.