Answer(s):
Revising the area of a circle formula
We already know that the area of a circle is expressed as
.
- The "r" variable is known as the radius.
<h2><u>
Solving each problem given:</u></h2><h3>
Solving Problem 4:</h3>
We are given the radius of circle, which is 7 in. Let us substitute the radius in the formula. Once substituted, we can simplify the expression obtained to determine the area of the circle shown in the picture.

<u>Take π as 22/7</u>
<em> </em>



<h3>Solving Problem 5:</h3>
In this problem, we are given the diameter to be 24 kilometers. Since the radius of the circle is half the diameter, we can tell that the radius of the circle is 24/2 kilometers, which is 12 kilometers.

<u>Take π as 22/7</u>



<h3>Solving Problem 6:</h3>
We are given the radius of circle, which is 3.5 in. Let us substitute the radius in the formula. Once substituted, we can simplify the expression obtained to determine the area of the circle shown in the picture.

<u>Take π as 22/7</u>




Note: <em>The radius given in this problem was not clearly stated. If the radius I stated here, is incorrect, please notify me in the comments. Thanks!</em>
Learn more about area of circles: brainly.com/question/12414551
Answer:
0.448 seconds
Step-by-step explanation:
d = -16t² -4t + 412
find t when d = 407
substituting d = 407 into the equation:
407 = -16t² -4t + 412 (subtract 407 from both sides)
-16t² -4t + 412 - 407 = 0
-16t² -4t + 5 = 0 (multiply both sides by -1)
16t² + 4t - 5 = 0
solving using your method of choice (i.e completing the square or using the quadratic equation), you will end up with
t = (-1/8) (1 + √21)= -0.70 seconds (not possible because time cannot be negative)
or
t = (-1/8) (1 -√21) = 0.448 seconds (answer)
I mean i don't know what to do but i made this graph online using https://www.mathpapa.com/algebra-calculator.html
5.441 inches every month I’m pretty sure