Will you answer my questioN? EXPLAIN HOW YOU DID IT AND SHOW WORK! THANK YOU?

a circular flower garden has a radius of 5 meters. it will be expanded so that its radius will be icreased by 2 meters. about how much greater will the expanded area? use 3.14 for pi.



a 12.6M2



b 50.3M2



c 75.4M2



D not here
Will you answer my questioN? EXPLAIN HOW YOU DID IT AND SHOW WORK! THANK YOU?
The area of circle is pi*r^2 (pi r square). Now let the increased radius be R and iniitial radius be r.

Area after expansion =pi*R^2 (pi R square)

Area before expansion =pi*r^2 (pi r square)

Increase in area =pi*R^2 - pi*r^2

=pi(R^2 - r^2)

=pi(R+r)(R-r)

=3*(7+5)(7-5), taking pi=3 aprox.

=3x12x2

=72 approx.

Since answer c alone is near to this value the answer is C.



Though the steps given are more the problem is done mentaly and not by writing these steps. The steps in mental calculations are

1. 7+5=12

2. 7-5=2

3. 3x12x2=72 and choose the answer.
Reply:the answer is c. You take the area of the second garden (Circular Area = pi times the radius squared) minus the area of the first garden. the first area would be 78.5. The next area would be 153.86 because the new radius is 7 and the radius squared is 49. 49 times 3.14 (pi) is 153.86. After that, you subtract the old area from the new one.



153.86

-78.5

--------

75.36 (rounded it is 75.4)
Reply:Do your own homework...
Reply:hey wen do u need dis?
Reply:the answer is C.but i think u should do this by ur self
Reply:first find the the area using pi-r(squared) of the radius of 5, then do the same for the radius of 7 then subtract the two...
Reply:The formula for the area of a circle is pi * r2.



Plug in the 2 numbers u have.



Subtract one from the other.



Piece of cake.
Reply:do your homework yourself
Reply:i know but im not telling...LOL
Reply:The only way you will succeed is if you try instead of just copying the answer. Trust me-i would know-i get copied from everyday at school.
Reply:the formula to be used is pi X r squared = area So, the first garden is pi 3.14 X r squared or 25 = 78.5

After being expanded 2 meters the formula would be 3.14 X 49 (7X7) or l15.86. Subtract the second the first area 78.5 from the second area ll5.86 and the answer is 75.36 rounded to 75.4.