Answer:
Step-by-step explanation:
= 3x(2x^2 - 4x - 5) - 6(2x^2 - 4x - 5)
= 6x^3 - 12x^2 - 15x - 12x^2 + 24x + 30
= 6x^3 - 24x^2 + 9x + 30 (answer)
Answer: 
Step-by-step explanation:
Given
The length of a rectangle is given by

and the breadth is given by

Perimeter is the sum of the sides of rectangle

Thus, the perimeter is given by
.
Answer:
Expressions A, E, and F
Step-by-step explanation:
In general, when negative integers are multiplied; if the negative integers are even, then the product would be positive. But if the negative integers are odd, then the product would be negative.
Thus,
A. (−5)(−0.4)(1.8) = (2.0)(1.8)
= 3.6
B. (-45)(-19)(-112) = (855)(-112)
= -95760
C. −1(5+17) = -1(22)
= -22
D. (−5)(−0.4)(1.8)(−3.25) = (2.0)(-5.85)
= -11.7
E. (-49)(-34)(-12)(-12) = (1666)(144)
= 239904
F. −1(3.5−7) = -1(-3.5)
= 3.5
Thus expressions A, E and F have positive products.