Answer:
C
Step-by-step explanation:
Calculate AC using Pythagoras' identity in ΔABC
AC² = 20² - 12² = 400 - 144 = 256, hence
AC =
= 16
Now find AD² from ΔACD and ΔABD
ΔACD → AD² = 16² - (20 - x)² = 256 - 400 + 40x - x²
ΔABD → AD² = 12² - x² = 144 - x²
Equate both equations for AD², hence
256 - 400 + 40x - x² = 144 - x²
-144 + 40x - x² = 144 - x² ( add x² to both sides )
- 144 + 40x = 144 ( add 144 to both sides )
40x = 288 ( divide both sides by 40 )
x = 7.2 → C
Lets think of it this way:-
1/2 is one half
Whats half of 12? 6
Now, 7 is greater than 6, which means the fraction 7/12 is greater than 1/2
Answer: 7/12 is bigger
#1 There is no area of a cube. There is only a volume.
#2 The formula is

where s is the side.
Substitute 729 in V since that is the volume.

Take the cube root and you will get
9.
So the formula is
and the side is 9.
This is the concept of scale factors, we are required to calculate for the volume of the smaller solid if the larger solid has a volume of 1975.
Area scale factor=(linear scale factor)^2
thus;
Area scale factor=(area of larger solid)/(area of smaller solid)=1057/384
linear scale factor=√(1057/384)=5.7019
the volume scale factor=(linear scale factor)^3=[volume of larger solid]/[volume of smaller solid]
The volume scale factor=(5.7019)^3=185.3772
therefore;
volume of smaller solid=[volume of larger solid]/[volume scale factor]
=1795/185.3772
=9.683
The answer is 9.683 yd^3