Answer:
The speed of the wave at the given wavelength and frequency is 60 m/s.
The given parameters;
wavelength of the wave, λ = 0.5 m
frequency of the wave, f = 120 Hz
The speed of the wave is calculated by applying general wave equation as shown below;
v = fλ
where;
v is the speed of the wave
v = 120 x 0.5
v = 60 m/s
Thus, the speed of the wave at the given wavelength and frequency is 60 m/s.
Answer:
There are two ways to solve this question. The faster way is to multiply each side of the given equation by ax−2 (so you can get rid of the fraction). When you multiply each side by ax−2, you should have:
24x2+25x−47=(−8x−3)(ax−2)−53
You should then multiply (−8x−3) and (ax−2) using FOIL
("First, Outer, Inner, Last")
24x2+25x−47=−8ax2−3ax+16x+6−53
Then, reduce on the right side of the equation
24x2+25x−47=−8ax2−3ax+16x−47
Since the coefficients of the x2-term have to be equal on both sides of the equation, −8a=24, or a=−3.
The other option which is longer and more tedious is to attempt to plug in all of the answer choices for a and see which answer choice makes both sides of the equation equal. Again, this is the longer option, and I do not recommend it for the actual SAT as it will waste too much time.
soo the final answer is B -3