Answer:
D
Step-by-step explanation:
group them first :
( x3+5x2) and ( -6x-30)
then simply by gcf ( greatest common factor) :
x2(x+5) and -6(x+5)
and just add them together:
x2(x+5)-6(x+5)
bonus :
it can be written as (x2-6)(x+5)
Answer:

Step-by-step explanation:
You have the following quadratic equation given in the problem:

You must make the equation equal to zero, as following:

Add like terms:

Now, to factor the equation, you must find two numbers whose sum is -2 and whose product is -15. Therefore, you have:

Let S be the sum,
S = 2 + 4 + 6 + ... + 2 (n - 2) + 2 (n - 1) + 2n
Reverse the order of terms:
S = 2n + 2 (n - 1) + 2 (n - 2) + ... + 6 + 4 + 2
Add up terms in the same positions, so that twice the sum is
2S = (2n + 2) + (2n + 2) + (2n + 2) + ... + (2n + 2)
or
2S = n (2n + 2)
Divide both sides by 2 to solve for S :
S = n (n + 1)
A)Theorem. every theorem can be proved.