Answer:
15x - 21
Explanation:
-3(-5x+7)
you sidtribute the 3 to both numbers by multiplying both the -5 and the 7 by -3
-3 x -5x = 15x (remember, a negative times a negative equals a positive)
-3 x 7 = -21 (A negative times a positive equals a negative)
15x - 21