Step-by-step explanation: So we know that area of a circle is pi times r^2 so if we reverse that formula it would be square root of 16 pi which would be 4 pi and divide by pi so the radius is 4. And we know that the formula for circumference is 2 times pi times r, so 2 times 4 times pi is 8 pi. 8 pi is the cIrcumference! :)

7 0

3 years ago

GEO, TRIGONOMETRY! 45 POINTS AND BRAINLIEST FOR CORRECT ANSWER. NEED HELP ASAP PLEASE :) Isabell is standing at the top of a wat

IRINA_888 [86]

Answer:

h ≈ 39 ft

Step-by-step explanation:

When we draw out a picture, we should see that we have to use cos∅ to solve this:

cos31.66° = x/46

46cos31.66° = x

x = 39.1542

5 0

3 years ago

Determine whether a quadratic model exists for the set of values below. If so, write the model. f(0) = -4, f(3) = -19, f(-1) =

Vikentia [17]

Answer:

A) The model exists: f(x) = -3x^2 +4x -4

Step-by-step explanation:

A quadratic model will always exist for 3 given points, provided they are not on a line. In that case, a linear model is appropriate.

Here, the slope between -1 and 0 is positive, and the slope between 0 and 3 is negative. Thus, we know these points are not collinear, and a model must exist.

The model is most easily found using a quadratic regression tool. Such is shown in the attachment. It tells us that ...

f(x) = -3x^2 +4x -4

7 0

2 years ago