3A+2B=20
2A+B=13 ➡×(-2)➡-4A-2B=-26
3A+2B-4A-2B=20-26
-A=-6 ➡A=6
2(6)+B=13➡B=1
Probably c or d it will probably be wrong though
The largest number that divides 63, 84, and 105 evenly is 21.
David can put 21 of each kind of tile in a row.
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These numbers are 3*21, 4*21, and 5*21, respectively.
Answer:1,2,5
Step-by-step explanation: