You have the following expression:
-3(-5)(-4)
In order to multiply the previous expression you first take into account the multiplication of signs. In this case you have - x - x -, that is, minus multiplied by minus multiplied by minus, the result for the sign of this multiplication is minus.
Next, you take into account the multiplication of numbers, 3 x 5 x 4 = 60
The answer is the previous obtained number with the obtained sign, that is:
-3(-5)(-4) = - 60
step by sptep:
-3(-5)(-4) = -3(20) = - 60
First of all, you multiply -5 by -4, the result of this is 20 (minus multiplied by minus is positive). Next, you multiply -3 by 20. In this case you have the multiplication of a negative number by a positive, so, the solution is a negaive number (minus mulitplied by positive is equal to minus). The result of -3 by 20 is -60.