What is a1? what is d? what’s the equation? what is a7? what is a59?

a1 = 2

d = 3

an = 2 + (n - 1) * 3

a7 = 20

a59 = 176

Steps:

a1 is the initial value (when n equals 1), and since there are 2 crosses, it is 2.

d is the added value to each amount of crosses. And since the second amount is 5 and the third amount is 8, we can determine that each n is adding 3 crosses, therefore making d = 3.

The equation is simply plugging in the values for a1 and d.

A7 is simply plugging in 7 for n in the equation and solving for it. So;

a7 = 2 + (7 - 1) * 3

a7 = 2 + 6 * 3

a7 = 2 + 18

a7 = 20

And same thing as the last for 59 except substitute 59 in for where you put 7;

a59 = 2 + (59 - 1) * 3

a59 = 2 + 58 * 3

a59 = 2 + 174

a59 = 176