Answer:
9.3
Step-by-step explanation:
35-7=28
28 divided by 3 = 9.3
Or $9 and 3 cents

so.. let's us eliminate, say "z" first, so for that, let's pick the 1s and 2nd equations there

so, that's our first two-variables resultant
let's pick other two, and again, eliminate the same "z" variable, this time, let's use the 2nd and 3rd equations

now, we have two two-variables equations, let's use them then
and say, we'll eliminate the "y" variable from them

Answer:
the first difference are all 20.
since the first differences of this relation are constant, it is a linear relation
You didnt give the sizes of the ribbon so let me help you out. You have to divide the size by total cost, bringing you to the cost per one whatever unit you are using.