12x-3y=21
4x-y=7
I hope this helps
Answer:
66.2 i think sorry if im off
Step-by-step explanation:
I came up with 1.3 hours.. Not sure if that's right but it would make sense. How did you figure it?
Actually, the "slant height" is 4, but the vertical height or "altitude" of the equilateral triangle is not 4
but anyway.....

and the volume, is the area of the triangle, times the length, so, whatever you get for the area of the triangle * 10