Simplify (7x^-4)(2y^8)(-3x^10)(-5y^-6)

$(7 x^{- 4}) (2 y^{8}) (- 3 x^{10}) (- 5 y^{- 6})$

Multiply $x^{- 4}$ by $x^{10}$ by adding the exponents.

Move $x^{10}$ .

$7 (x^{10} x^{- 4}) (2 y^{8}) \cdot - 3 (- 5 y^{- 6})$

Use the power rule $a^{m} a^{n} = a^{m + n}$ to combine exponents.

$7 x^{10 - 4} (2 y^{8}) \cdot - 3 (- 5 y^{- 6})$

Subtract $4$ from $10$ .

$7 x^{6} (2 y^{8}) \cdot - 3 (- 5 y^{- 6})$

Multiply $y^{8}$ by $y^{- 6}$ by adding the exponents.

Move $y^{- 6}$ .

$7 x^{6} (2 (y^{- 6} y^{8})) \cdot - 3 \cdot - 5$

Use the power rule $a^{m} a^{n} = a^{m + n}$ to combine exponents.

$7 x^{6} (2 y^{- 6 + 8}) \cdot - 3 \cdot - 5$

Add $- 6$ and $8$ .

$7 x^{6} (2 y^{2}) \cdot - 3 \cdot - 5$

Rewrite using the commutative property of multiplication.

$7 \cdot 2 x^{6} y^{2} \cdot - 3 \cdot - 5$

Multiply $7$ by $2$ .

$14 x^{6} y^{2} \cdot - 3 \cdot - 5$

Multiply $- 3$ by $14$ .

$- 42 x^{6} y^{2} \cdot - 5$

Multiply $- 5$ by $- 42$ .

$210 x^{6} y^{2}$