3x² - 21
Factor 3 from both terms:
3 (x² - 7)
To me, that's as far as you should need to go. But if you want to get
completely carried away, you could go one step further, since you have
the difference of two squares:
3 (x + √7) (x - √7)
Of course, there's no end now, because the last binomial could be
considered another difference of two squares, so you'd have to
factor that too:
3 (x + √7) (√x + ⁴√7) (√x - ⁴√7)
but to me, this would be nonsense.
Answer:


Step-by-step explanation:
<u>First, Let's solve for x in -2x+2y=-4:</u>

<u>Subtract 2y from both sides:</u>


<u>Divide both sides by -2:</u>


<u>Now, we'll substitute x=y+2 to 3x+3y=-18:</u>

→ let x=2+y

<u>Simplify:</u>

<u>Now, let's solve for y in 6+6y=-18</u>

<u>Subtract 6 from both sides:</u>


<u>Divide both sides by 6:</u>


<u>Now, substitute y=-4 into x=2+y:</u>

→ let y = -4


Therefore, x=-2 and y=-4.
<u>_____________________________________</u>
Please show a picture of the diagram.
Answer: 5in
Step-by-step explanation:
1/3x8/8=8/24
1/8x3/3=3/24
8-3=5
Answer:
The answer is 
Step-by-step explanation:
Assuming the snowball is a perfect sphere, then if A denotes the surface area and D the diameter then:

Differentiating wrt r we have:

We are told that
and we want to find 
By the chain rule we have:

∴
∴
When D=10 then

The sign (-) shows that the D is decreasing.