A circular mirror is surrounded by a square metal frame. the radius of the mirror is 5x. the side length of the metal frame is 15x what is he area of the metal frame?

Since the side of the square frame is 15x, the area of the frame in whole would be:

(15x) ² = 225x²

Now if we subtract out the circle mirror with a radius of 5x, we get:

225x² - πr²

225x² - π (5x) ²

225x² - π25x²

We can factor out a 25x² and get:

25x² (9 - π)