Another algebra questionn ???!!!?

Question

OK, i need help with another two algebra questions ...

1. Area of a circle: ((pie sign)r if r=28
Use the fraction 22/7 as an approximate value for pie.
I got an answer of 2362.2 for this problem.

2. Perimeter: 2(r+h)+(pie)r
if r=2.00 and h-3.00
use 3.14 as an approx. value for pie.
i pretty confused about this one ... can someone explain it to me???

** thanks!!!!

Answer 1

1. The answer is 88. (22/7) x 28 = 616/7 = 88

2. Substitute all the number into the equation and multiply it out. 2(2+3) + (3.14)(2) = 16.28

Hope this helps!

Answer 2

pi r means pi times r. Pi: 22/7 is 22 divided by 7 which is just a little over 3. (3.14, same as 22/7 is pi), so if you multiply 28 by a little over 3, you are going to get a smaller number than what you got. You can just use 3.14 and multiply it times 28 and when you get your 4-digit number, put the decimal point over 2 numbers to the left.


Add r and h together first , because they're in brackets, then multiply the number you got times 2 - circle your answer. Then multiply 2 times pi and when you get that number, circle it. Add the two circled numbers together. circles help to keep up with the numbers that are added, last.

Answer 3

The area of a circle is pi*(r squared) if r=28, then r squared is 784. 784 * 22/7 is 2464.

Perimeter (same as circumference?) of a circle is pi* diameter. Diameter = 2 * radius. Not sure what "h" refers to. A circle is totally defined by a center point and a radius. If you are talking the perimeter of a rectangle, you just add up the sides. No pi involved.

Answer 4

pi X r^2 = area so, 28 X 28X22/7 = 2,464

next one is 16.28. looks like the perimeter you want is of a semicircle sitting on top of a rectangle. the height of the rectangle is "h" and the radius of the circle is "r". so your formula would give the perimeter of this object.

Answer 5

to do this, you want to aspect f(x): f(x)=x^3-x f(x) = x(x² - a million) f(x) = x(x-a million)(x+a million) For f(x) to be 0, one in each of those aspects desires to be 0: x = 0 or x - a million = 0 or x + a million = 0 x = 0 or x = a million or x = -a million So, all values of x making f(x)=0 are -a million, 0, and a million. wish that helps :)