Write the sum using sigma notation: $-3-9-27+\ldots-6561$
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So, the sum using sigma notation is $\Sigma_{n=0}^{8} (-3)^n * -3$.

Steps

Step 1 ：The given series is a geometric series where each term is multiplied by -3 to get the next term.

Step 2 ：The general form of a geometric series is $a + ar + ar^2 + ar^3 + ... + ar^n$, where $a$ is the first term and $r$ is the common ratio.

Step 3 ：In this case, $a = -3$ and $r = -3$.

Step 4 ：We can write the sum using sigma notation as follows: $\Sigma_{n=0}^{8} (-3)^n * -3$.

Step 5 ：This is because the first term is when $n=0$, and the last term, -6561, is when $n=8$ (since $-3^8 = -6561$).

Step 6 ：So, the sum using sigma notation is $\Sigma_{n=0}^{8} (-3)^n * -3$.