Answer:
Here is the rule: when a and b are not negative
√(ab) = √a × √b
Example: simplify √8
√8 = √(4×2) = √4 × √2 = 2√2
(Because the square root of 4 is 2)
In other words 2 x 4 = 8 = √2 x 4 but 4 can be simplified more (2 x 2) so 2 (previous 4) moves to the left of the square root leaving 2√2
To simplify a square root: make the number inside the square root as small as possible (but still a whole number)
or you can use a simplifying square root calculator.
Answer:
C) 
Step-by-step explanation:
The formula for area is
A=pi * radius ^2
If the diameter is 40, the radius is 20
Therefore

Answer:
B), x=-1, y=-2, z=1.
Step-by-step explanation:
Since the sweater is now 30% off, that means it is selling for 70% of it's original price ( 100% - 30% = 70%).
Multiply the original price by 70%:
52 x 0.70 = 36.40
The sale price is $36.40