PLEASE HELP WHAT IS THE UNIT RATES OF THIS

#7

1. Find the volume of the pyramid (l×w×h/3); you should get 64cm³

2. Find the volume of the cube (l×w×h); you should get 512cm³

3. Add the two products; the glass paperweight's volume is 576cm³

#8

1. Find the surface area (SA) of the cube (area of one square×5); it is 320cm²

2. Find the SA of the pyramid (exclude the square base); it is 80cm² ((slant height×(length/2))×4)

3. Add the surface areas; the sum should be 400cm²

or

step-by-step explanation:

we need to solve for 'x' the following equation:  

we have that:

⇒

⇒ ⇒

factorizing, we get that:

  ⇒

then, the solutions are: or

nothing extraneous has been found!