its 14n+21. 7×2n is 14n, and 3×7 is 21
Answer:
[tex]7(2n+3)=14n+21[/tex]
Step-by-step explanation:
[tex]7(2n+3)=(7*2n)+(7*3)\\\\ 7*2n=14n\\ 7*3=21\\ \\ 7(2n+3)=14n+21[/tex]
