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lara [203]
3 years ago
9

47.Explain sound needs a medium for propagation​

Mathematics
1 answer:
Ghella [55]3 years ago
4 0

Answer:

Sound needs a material medium for their propagation like solid, liquid or gas to travel because the molecules of solid, liquid and gases carry sound waves from one point to another. Sound cannot progress through the vacuum because the vacuum has no molecules which can vibrate and carry the sound waves.

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Write an equation in slope-intercept form given the point and the slope. Then graph the equation.
liq [111]

Answer:

y=-3/4x+5.5

Step-by-step explanation:

5 0
3 years ago
There are 11 girls and 14 boys in Mrs. Smith's fourth grade class, as shown in the
WINSTONCH [101]
79% the second choice
8 0
3 years ago
If y = 8x − 2, which of the following sets represents possible inputs and outputs of the function, represented as ordered pairs?
Nataly [62]
You just need to try with all of the pair f.ex
0,-2 -> put 0 in the x-> y=8*0-2=-2 so ok it is q possible pair of the function..
You try every pair till you find set where all the pairs fit
So set 1
1 and 6: 8*1-2=6 ok
2 and 14 : 8*2-2=14 ok
Hope I could help
6 0
3 years ago
Read 2 more answers
Based on Pythagorean identities, which equation is true? A. Sin^2 theta -1= cos^2 theta B. Sec^2 theta-tan^2 theta= -1 C. -cos^2
Arturiano [62]

Answer:

D

Step-by-step explanation:

our basic Pythagorean identity is cos²(x) + sin²(x) = 1

we can derive the 2 other using the listed above.

1. (cos²(x) + sin²(x))/cos²(x) = 1/cos²(x)

1 + tan²(x) = sec²(x)

2.(cos²(x) + sin²(x))/sin²(x) = 1/sin²(x)

cot²(x) + 1 = csc²(x)

A. sin^2 theta -1= cos^2 theta

this is false

cos²(x) + sin²(x) = 1

isolating cos²(x)

cos²(x) = 1-sin²(x), not equal to sin²(x)-1

B. Sec^2 theta-tan^2 theta= -1

1 + tan²(x) = sec²(x)

sec²(x)-tan(x) = 1, not -1

false

C. -cos^2 theta-1= sin^2

cos²(x) + sin²(x) = 1

sin²(x) = 1-cos²(x), our 1 is positive not negative, so false

D. Cot^2 theta - csc^2 theta=-1

cot²(x) + 1 = csc²(x)

isolating 1

1 = csc²(x) - cot²(x)

multiplying both sides by -1

-1 = cot²(x) - csc²(x)

TRUE

3 0
3 years ago
Số tiếp theo (next number?): 25 50 99 196 388
Delvig [45]

Answer:

The correct answer is - 768.

Step-by-step explanation:

The given question is based on a specific pattern present in between the numbers in the given series -

Series = 25 50 99 196 388

to find - next number in series

let us find the relation between the initial two number:

25 - 50, here number 50 is two times of 25 or (x*2-0)

relation between 2nd and 3rd number:

50 - 99, here 99 is two times of 50 minus 1 or (x*2-1)

relation between 3rd and 4th number:

99 - 196, here 196 is two times of 99 minus 2 or (x*2-2)

relation between 4th and 5th number:

196 - 388, here 388 is the two times of 196 minus 4 or (x*2-4)

So on this pattern, the next number would be = x*2-8

388*2-8

= 768

5 0
3 years ago
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