Answer: Choice A, x=-4
Step-by-step explanation:
1. 9x−(3x+9)=2x−25
2. 9x-3x-9=2x-25
3. 6x-9=2x-25
4. 6x-9=2x-25
-2x -2x
5. 4x-9=-25
+9 +9
6. 4x=-16 (divide both sides by 4)
7. x=-4
Answer:

Step-by-step explanation:
1 n=0
1 1 n=1
1 2 1 n=2
1 3 3 1 n=3
1 4 6 4 1 n=4
1 5 10 10 5 1 n=5
1 6 15 20 15 6 1 n=6
This is where n is the exponent in
.

Now we want to expand:
or we we can rewrite as
.
Let's replace
with
and
with
in the expansion:



Let's simplify a bit:


Answer:
D. 1662 cm
Step-by-step explanation:
A=πr2=π•23≈1661.90251cm²
which is 1661.9
but of course you have to round up for 1662 cm :)