You should draw a picture to visualize the problem easier.
The circumference of inner circle = 44 ft
That means the radius of the inner circle:
2*pi*r = 44
r = 44/(2pi) = 22/pi
Using the picture you hopefully drew, we see that the radius of the outer circle:
22/pi + 2
To figure out the circumference of the outer circle:
2pi*(22/pi + 2) = 44 + 4pi
So how much bigger is the the circumference of the outer circle than the inner circle?
44 + 4pi - 44 = 4pi
It is 4pi bigger or 4 * (3.14) = 12.56 feet
The transformation is ISOMETRY.
In mathematics, an isometry<span> (or congruence, or congruent transformation) is a distance-preserving transformation between metric spaces, usually assumed to be bijective. A composition of two opposite </span>isometries<span> is a direct </span>isometry<span>. A reflection in a line is an opposite </span>isometry<span>, like R </span>1<span> or R </span>2<span> on the image.</span>
Answer:
Mr.Lin's present age is 30 years now. His son is 8 years old now.
Step-by-step explanation:
Let L = Mr.Lin's present age,
S = his son's present age.
First equation is
L + S = 38. (1)
The second equation is
L + 3 = 3*(S+3) (2) ("In three years' time, Mr.Lin will be three times as old as his son.")
From (1), express S = 38-L and substitute it into (2). You will get
L + 3 = 3*((38-L)+3), or
L + 3 = 114 - 3L + 9,
4L = 114 + 9 - 3,
4L = 120,
L = 30.
