Find the Exact Value (-30(-7))-(210(-3))

$(- 30 (- 7)) - (210 (- 3))$

Simplify each term.

Multiply $- 30$ by $- 7$ .

$210 - (210 (- 3))$

Multiply $210$ by $- 3$ .

$210 - - 630$

Multiply $- 1$ by $- 630$ .

$210 + 630$

Add $210$ and $630$ .

$840$