5 Multiply 3.(-5.(-3).(-10)=

it helps if you ask a meaningful question.

it's hard to interpret the mix of words and unbalanced parentheses.

If the "multiply" means to multiply 5 by the rest of the expression, and the dots also mean multiplication, then, assuming a final right paren:

5(3)((-5)(-3)(-10)) = (5)(3)(-150) = -2250