<span>(x-3)(x^2+9)
or
x^3 -3x^2 + 9x - 27
First, let's see about factoring x^4 - 81. Cursory examination indicates that it's the difference of two squares and so it initially factors into
(x^2 - 9)(x^2 + 9)
And the (x^2 - 9) term is also the difference of 2 squares so it too factors into:
(x - 3)(x + 3)
So a partial factorization of x^4 - 81 is:
(x - 3)(x + 3)(x^2 + 9)
The (x^2 + 9) term could be factored as well, but that's not needed for this problem, and so I won't do it.
Now we can divide (x-3)(x+3)(x^2+9) by (x+3). The (x+3) terms will cancel and we get as the result
(x-3)(x+3)(x^2+9) / (x+3) = (x-3)(x^2+9)
We can leave the answer as (x-3)(x^2+9), or we can multiply it out, getting:
x^3 -3x^2 + 9x - 27</span>
Step-by-step explanation:
area of ∆ = .5*b*h
b= x+5
h= x-5/2
let's do (x+5) * (x-5/2)
x^2+5x-5/2x-25/2
x^2+5/2x-25/2
area = .5x^2+5/4x-25/4
Answer:
1000 grams
Explanation:
There are 1000 grams in one kilograms
Set it up as a ratio. $5.25/5 = $1.05 per notebook
Then solve your equation by multiplying the cost by 3. 3 * $1.05 = $3.15
1cm = 2m
=> 1cm = 200cm
2.5cm = 2.5 × 200cm = 500 cm = 5m
So, the length of window is 500cm or 5m.
