Answer:
Step-by-step explanation:
The function that could model this periodic phenomenon will be of the form
The tide varies between 3ft and 9ft, which means its amplitude is
and its midline is
.
Furthermore, since at the tide is at its lowest ( 3 feet ), we know that the trigonometric function we must use is
.
The period of the full cycle is 14 hours, which means
giving us
With all of the values of the variables in place, the function modeling the situation now becomes
Answer:
B, C, and D.
Step-by-step explanation:
Let's go through each answer choice.
A: To find the slope of a line from two points, we use this formula: . Plugging in the values (-2,0) and (2, -4), we get:
Because option A says the slope is 1, but we got -1, option A is false.
B: To find the y-intercept, we use this formula:
Since we know the value of b is the y-intercept, we could write the y-intercept as (0,-2). Therefore, option B is true.
C: The equation of a line (in slope-intercept form) is y = mx + b, where y - y-coordinate, m = slope, x = x-coordinate, and b = y-intercept. Since we already solved for the y-intercept and slope, let's plug in those values:
As you can see, the equation we got here matches the one in option C, meaning it's true.
D: We know that a point is written like this: (x, y). If the x-coordinate is not zero but the y-coordinate is, then it's the x-intercept. Since the question says that (-2,0) is one of the points the line passes through, and option D says that the x-intercept is (-2,0), it's true.