Question

Select all the expressions that are equivalent to the polynomial below.

(4x+5)(-3x-1)



A.(-16x2 + 10x - 3) + (4x2 - 29x - 2)
B. 3(x - 5) - 2(6x2 + 9x + 5)
C. 2(x - 1) - 3(4x2 + 7x + 1)
D.(2x2 - 11x - 9) - (14x2 + 8x - 4)
E. (-15x2 + 9x - 10) + (3x2 - 10x - 5)
F.(4x2 - 13x - 7) - (16x2 + 9x - 5)

Answer 1

A. C. And D. Are same

Explanation:

(4x+5)(-3x-1)

Applying distributive law

4x(-3x-1)+5(-3x-1)

Again applying distributive law in both the brackets

`-12x^2-4x-15x-5`

Adding the terms having same power of x

`-12x^2-19x-5`

1.
`-16x^2+10x-3+(4x^2-29x-2 )`

Simplifying the terms containing the same power of x

`-16x^2+10x-3+4x^2-29x-2`

`-12x^2-19x-5`

Hence it is true

2.
`3(x-5)-2(6x^2+9x+5)`

`3x-15-12x^2-18x-10`

`-12x^2-15x-25`

False

3.
`2(x-1)-3(4x^2+7x+1)`

`2x-2-12x^2-21x-3`

`-12x^2-19x-5`

True

4.
`2x^2-11x-9-(14x^2+8x-4)`

`2x^2-11x-9-14x^2-8x+4`

`-12x^2-19x-5`

True

5.
`-15x^2+9x-10+3x^2-10x-5`

`-12x^2+19x-15`

False

6.
`4x^2-13x-7-(16x^2+9x-5)`

`4x^2-13x-7-16x^2-9x+5`

`-12x^2-22x-2`

False

Answer 2

(4x+5)(-3x-1)=
-12x²-19x-5
So, you answers would be:
A. (-16x²+10x-3) + (4x²-29x-2)
D. (2x²-11x-9) - (14x²+8x-4)
Have a nice day! ♪