How much does a glass cube with a side of 5-cm weigh if 1cm of glass weighs 2 2/5 grams?

  300 grams

Step-by-step explanation:

The volume of the glass cube is ...

  V = s³ = (5 cm)³ = 125 cm³

This is 125 times the volume of a 1-cm cube, so the weight is 125 times as much:

  125 × (2 2/5 g) = 300 g

The glass cube weighs 300 grams.

d

step-by-step explanation:

given the equation is 8+9z=-6, the first step would be to subtract the 8 from both sides:

8+9z-8=-6-8

since 8 minus 8 = 0, this would cancel out the 8. and since -6 minus 8 equals -14, the equation would look like this

9z = -14