Answer:
or 
Step-by-step explanation:
You need to complete the square before you can take the square root of both sides.
Subtract 10 from both sides.
To complete the square, you need to add the square of half of the x-term coefficient to both sides.
The x-term coefficient is 7. Half of that is 7/2. Square it to get 49/4. Now we add 49/4 to both sides of the equation.
Now we use the square root property, if
, then
or 
or 
or
Answer:
10.69
Step-by-step explanation:
We must first know that the angle of refraction is given by the following equation:
n_water * sin (A_water) = n_air * sin (A_air)
where n is the refractive index, for water it is 1.33 and for air it is 1.
The angle (A) in the air is 22.8 °, and that of the water is unknown.
Replacing these values we have to:
1.33 * sin (A_water) = 1 * 0.387
sin (A_water) = 1 * 0.387 / 1.33
A_water = arc sin (0.2907) = 16.9 °
now for the tank depth:
h = D / tan (A_water)
D = 3.25
Replacing
h = 3.25 / tan 16.9 °
h = 10.69
Therefore the depth is 10.69 meters.
The correct answer would be A.36.
Hope this helps;)
Answer:
the correct answer would be 13.5
