Answer:
B.
Step-by-step explanation:
To simplify something that looks like 
you would multiply the top and bottom by the conjugate of the bottom. So you multiply the top and bottom for this problem I just made by:
.
If you had 
, then you would multiply top and bottom the conjugate of which is 
.
The conjugate of a+b is a-b.
These have a term for it because when you multiply them something special happens. The middle terms cancel so you only have to really multiply the first terms and the last terms.
Let's see:
(a+b)(a-b)
I'm going to use foil:
First: a(a)=a^2
Outer: a(-b)=-ab
Inner: b(a)=ab
Last: b(-b)=-b^2
--------------------------Adding.
a^2-b^2
See -ab+ab canceled so all you had to do was the "first" and "last" of foil.
This would get rid of square roots if a and b had them because they are being squared.
Anyways the conjugate of 
is
.
This is the thing we are multiplying and top and bottom.
C=1500+4x where x is cds, C is cost
R=10x where R is revenue
then, P=R-C
P=10x-1500-4x
P=6x-1500
set P=0
1500=6x
x=250
check, C=1500+4*250, R=10*250
C=250, R=250
They need to sell 250 cds before they make profit
The best estimate for 1,374 is 1,400 and the best estimate for 6 is 10. This is because anything that is 5 and above you change it. Example: 16 the best estimate for 16 is 20 because 6 is above 5. And when a number is 4 and below you change the number below. Example: 12 the best estimate for 12 is 10 because 2 is below 4. And when the number is perfect like 10, you can keep the number the same. Example:10,20,30,40,50,60etc.
Hope this Helped! :)
Answer:
B: 144 yd²
Step-by-step explanation:
It's a square pyramid : Base area 8 x 8 = 64
4 side area:((8 x5) /2) x 4 = 80
Total area: 64 +80 = 144
