Answer:
The answer to your question is the letter C
I think it's the answer C, because in the second and third pairs, the -2 are the same.
Answer:
(a)


(b)


(c)


Step-by-step explanation:
(a) This is a sequence of consecutive number



(b) This is a sequence of 2 to the power of n - 1. The next number is twice time of this number



(c) This is factorial sequence. Where the next number is this number multiplied by 



Answer:
y-intercept is 30
Step-by-step explanation:
Given the model
comparing this model to the equation of a straight lines we can get the y- intercept

The y- intercept is 30 which is the constant factor and it describes to us about the one-time registration fee of $30.
Answer:
x = 387
Step-by-step explanation:
The wind acts in the opposite direction to the plane when the time is longer.
The wind acts in the same direction as the plane when the time is shorter.
Equation
d = r*t
Givens
- d = 1720
- x = plane's speed
- y = wind speed
- t1 = 5 hours
- t2 = 4 hours.
Substitution
- d = (x + y) * t
- 1720 = (x + y) * 4
- 1720 = (x - y) * 5
Since the two distances are the same, you can equate the right hand sides.
- (x + y) * 4 = (x - y)*5 Remove the brackets.
- 4x + 4y = 5x - 5y Add 5y to both sides
- 4x + 4y + 5y = 5x - 5y + 5y Combine all the terms.
- 4x + 9y = 5x Subtract 4x from both sides
- 9y + 4x - 4x = 5x - 4x Combine
- 9y = x
Now use one of the given equations with the distance
- 1720 = (x + y)*4 Substitute 9y for x
- 1720 = (9y + y) * 4 Combine
- 1720 = 10y * 4 Multiply the right
- 1720 = 40y Divide by 40
- 1720/40 = 40y/40 Do the division
- 43 = y y = wind speek
- 9y = x x = 9*y
- 9*43 = x
- x = 387 miles per hour.