Answer: x is 20
Step-by-step explanation:
This is ratio
a : c = b : x and d : unknown
a : c = 9 : 12 = 3 : 4 which is 9/12
b : x = 15 : x which is 15 / x
So the proportion will be :
3/4 = 15/x
So Cross multiplying
3x = 90
Divide both side by 3
x = 90/3
x = 20
Answer:
a) Frequency remains constant
b) Wavelength remains constant
c) speed of the wave remains constant
d) Intensity decreases
e) amplitude of its electric field decreases
Explanation:
a) Frequency can be defined as the number of crests that pass a fixed point in the medium in unit time. It is the source of the wave that will determine the frequency. If the small source is changed to a bigger and faster one then the frequency will change. In our case, there is no change of source of wave, so the frequency remains constant.
b) The speed of of the wave is directly proportional to the wavelength. If we double the speed, the wavelength also doubles. Since the speed has not been doubled in our case, the wavelength will remain constant.
c) As indicated in b) since the wavelength is proportional to speed and it has not changed in our case, then the speed remains constant.
d) The intensity of a wave decreases as it moves further away from the source.
e) The intensity is related to the amplitude. Since the intensity decreases, the amplitude also decreases.
I want to say that the answer is A but i don't know I hate word problems.
ANSWER
EXPLANATION
In the given, diagram G is called the centroid of the triangle because it is the point where all the three medians of the triangle intersect.
This point, G, divides the medians in the ratio,
This implies that,
or
We substitute
to get,
This will give us,
But,
This implies that,
Alternatively,
Or
This gives us,
