Answer:
n-8
Step-by-step explanation:
The difference between a number and 8
Difference is subtraction
Let the number be n
n-8
Answer:
$3.23
Step-by-step explanation:
1.71 ÷ 18 = 0.095 = 9.5%
9.5% × 34 = 3.23
7/8 is ur answer because
it can be cut into smaller parts
Answer:
A) y^3+27
Step-by-step explanation:
There are two ways of solving this problem:
1. Recognizing this as the factored form of the sum of perfect cubes
2. Distribute and add the like terms.
1. In order to distribute we must multiply y by y^2-3y+9, and then 3 by y^2-3y+9:
![(y+3)(y^2-3y+9)=y(y^2-3y+9)+3(y^2-3y+9)](https://tex.z-dn.net/?f=%28y%2B3%29%28y%5E2-3y%2B9%29%3Dy%28y%5E2-3y%2B9%29%2B3%28y%5E2-3y%2B9%29)
![y(y^2-3y+9)+3(y^2-3y+9)=y^3-3y^2+9y+3y^2-9y+27](https://tex.z-dn.net/?f=y%28y%5E2-3y%2B9%29%2B3%28y%5E2-3y%2B9%29%3Dy%5E3-3y%5E2%2B9y%2B3y%5E2-9y%2B27)
After we add the positive and negative 3y^2 and 9y, they will cancel out and be gone entirely:
![y^3-3y^2+9y+3y^2-9y+27=y^3+27](https://tex.z-dn.net/?f=y%5E3-3y%5E2%2B9y%2B3y%5E2-9y%2B27%3Dy%5E3%2B27)
2. You know how you can factor the difference of perfect squares?
As an example:
![a^2-b^2=(a+b)(a-b)](https://tex.z-dn.net/?f=a%5E2-b%5E2%3D%28a%2Bb%29%28a-b%29)
Well, not many people know this but you can actually factor both the sum and difference of perfect cubes:
![a^3+b^3=(a+b)(a^2-ab+b^2)](https://tex.z-dn.net/?f=a%5E3%2Bb%5E3%3D%28a%2Bb%29%28a%5E2-ab%2Bb%5E2%29)
![a^3-b^3=(a-b)(a^2+ab+b^2)](https://tex.z-dn.net/?f=a%5E3-b%5E3%3D%28a-b%29%28a%5E2%2Bab%2Bb%5E2%29)
Because we have these identities, we can easily establish here that we have the sum of perfect cubes, and that (y+3)(y^2-3y+9)= y^3+3^3 = y^3+27