Solve for a8 a_8=(4)(-6)^(8-1)

$a_{8} = (4) {(- 6)}^{8 - 1}$

Subtract $1$ from $8$ .

$a_{8} = 4 {(- 6)}^{7}$

Raise $- 6$ to the power of $7$ .

$a_{8} = 4 \cdot - 279936$

Multiply $4$ by $- 279936$ .

$a_{8} = - 1119744$