how do you write an expression for the number of _______ in figure __?

Question

this is the table in my question:

figure number, n    number of squares, s

          1                                 6

          2                                  9

           3                                 12

           4                                  15

i have to write an expression for the number of squares in figure n. which i dont know how to do

Answer 1

y=3*(n+1)

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