+0  
 
+1
87
3
avatar

There is a circle in the coordinate plane. If the radius doubles, the area increases by \(10\) units. Find the new radius of the circle

 Jan 18, 2022
 #1
avatar
+1

We can write a system of equations as a= pi*r^2 and a+10 = pi*(2r)^2. This is where a is the area and r is the radius. The new radius is 2r. Now we can simplify the second equation to a+10=4(pi*r^2). We can subtract the first equation from the second equation and get 10=3(pi*r^2) and r=sqrt(10/(3*pi)) so 2r = 2sqrt(10/(3*pi)).

You can blame me if I'm wrong but I think this is right.

 Jan 18, 2022
 #3
avatar+1635 
0

I gave you a plus for your concept. Kudos! smiley

jugoslav  Jan 19, 2022
 #2
avatar+1635 
0

There is a circle in the coordinate plane. If the radius doubles, the area increases by 10 units. Find the new radius of the circle.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Radius => r             New radius => 2r

A = r2pi                    An = (2r)2pi             (An = A + 10)

An - A = 10

(2r)2pi - r2pi = 10

 

smiley

 Jan 19, 2022

29 Online Users

avatar