What is the area of the pentagon shown?

Proceed as in example 3 in section 6.1 to rewrite the given expression using a single power series whose general term involves xk. ∞ n(n − 1)cnxn − 2 n = 2 − 4 ∞ ncnxn n = 1 + ∞ cnxn n = 0

What is the value of x in the this question ?

8litres of paint can cover 129.6 m². how much paint is required to paint an area of 243m²?