Each piece would be about 2.4 feet long. You find this out by dividing 7.2 and 3 which comes out to 2.4
Is it an isosceles triangle
343 is a cube root of 7. Its surface area is 7
I'm assuming you mean

we can factor that sum of perfect cubes from

into

so therefor

that is simpliest form
130 because 2 is less than 5