Answer:
20 longs, 9 units more than the 9 flats
Step-by-step explanation:
If Abby has 9 flats, she has 900 blocks of the 1109 she needs. The remaining 209 can be represented by ...
20 longs
9 units
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<em>Comment on the question</em>
We cannot see the model Abby has put together so far, so we don't know exactly what it takes to finish it. Any longs or units she already shows must be subtracted from the numbers above.
Well, variables are stuff like x and y because they can represent a number. They are variable in an equation. so if you have (3x^3)+(5X^2)+Y+9 then your variables are x X and Y (im assuming the capital X is there and not a typo) if that was a typo and meant to be lowercase, then its just a 2 variable with the x and y
