Use the formula to evaluate the series 3-9+27-81+

In the given series, we see that the first term is 3 and the common ratio between the succeeding terms is -3. To solve for the sum of the first 8 terms, we use the equation,

                                    Sum = (a1)(1 – r^n) / (1 – r)

Substituting the known terms,

                                    Sum = (3)(1 – (-3)^8)/(1 - -3) = -4920

Thus, the answer is -4920.

answer is 33

step-by-step explanation:

answer: bea's uncle is 25 years old.

step-by-step explanation:

given the equation , we can say that the variable "x" represents the age of bea's uncle. then to find his age, we need to solve for "x":

we must add 15 to both sides of the equation:

now we need to divide both sides of the equation by 3:

therefore, we can conclude that bea's uncle is 25 years old.