A group of students is arranging squares into layers to create a project. The first layer has 6 squares. The second layer has 12 squares. Which formula represents an arithmetic explicit formula to determine the number of squares in each layer?

a1 = 6; an = 6 + an − 1, n > 0

a1 = 6; an = 6 ⋅ an − 1, n > 0

a1 = 6; an = 6 ⋅ an + 1, n > 0

a1 = 6; an = 6 + an + 1, n > 0

Can we pls get the answer

Ur Mum

No.

The correct formula to represent an arithmetic explicit formula to determine the number of squares in each layer is:

a1 = 6; an = 6 + an − 1, n > 0

This formula indicates that the first term (a1) is 6, and each subsequent term (an) can be obtained by adding the previous term (an-1) by 6.

You are adding 6 tiles to the layer before it, so I expect to see something like

a(n-1) , not a(n+1)
That rules out the last 2.
The second says: "a new layer is 6 times that of the previous layer", which it clearly is not
The first one says: " a new layer adds 6 to the previous layer", so what do you think?