Evaluate the summation of 2 times negative 2 to the n minus 1 power, from n equals 1 to 7..

−256

−84

84

86

(D) 86

Step-by-step explanation:

According to the question, the equation will be= \sum_{n=1}^{7}2(-2)^{n-1}.

Now,substituting the values of n from 1 to 7 in the above equation, we have

\sum_{n=1}^{7}2(-2)^{n-1} =

=

=

=

Hence, the correct answer will be equal to 86.

it's d.

step-by-step explanation:

because: -1(4x + 1y) +2 (1x-3y) distribute each number into the parenthesis.

then you would get: -4x - 1y + 2x -6y combine like terms

and get: 2x -7y

hope my answer has you if not then i'm sorry.