Question

dude plz help
A circle has an area of 25pi Another circle has a diameter 5 times the first. What is the diameter of 2nd circle

Answer 1

Answer:

the Diameter of second circle is 50

Step-by-step explanation:

Area of first circle = 25 π

Diameter of first circle = d

Diameter of second circle= 5(Diameter of first circle) (because Another circle has a diameter 5 times the first)

We need to find diameter of 2nd circle.

First we find diameter of first circle.

The formula for area of circle is: $Area=\pi r^2$

We also know that: $Diameter = 2r$

First we will find radius and using diameter formula we can find diameter of the circle.

$Area=\pi r^2\\25\pi =\pi r^2\\r^2=\frac{25\pi}{\pi}\\r^2=25\\Taking\:square\:root\:on\:both\:sides\\\sqrt{r^2}=\sqrt{25}\\r=5$

So, radius of first circle is r = 5

Now, finding diameter of first circle:

$Diameter = 2r\\Diameter= 2(5)\\Diameter= 10$

So, Diameter of first circle = 10

Now, we know that diameter of second circle is 5 times the first

So, Diameter of second circle = 5(Diameter of first circle)

Diameter of second circle = 5(10)

Diameter of second circle = 50

So, the Diameter of second circle is 50