Answer/Step-by-step explanation:
[1] x+9+1+3x
Add the numbers
x + 10 +3x
Combine like terms
4x+10
Common factor
2(2x+5)
Solution = 2(2x+5)
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[2] 5a+6c+2a+3c
Combine like terms
7a+6c+3c
Combine like terms
7a+9c
Solution = 7a + 9c
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[3] 5n+6m+3n
Combine like terms
8n + 6m
Rearrange terms
6m + 8n
Solution = 6m+8n
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[RevyBreeze]