00:01
Hello, welcome to this lesson.
00:02
In this lesson we have a normal window that has a shape of a rectangle surmounted by a semicircle.
00:11
So here we have the perimeter of the window that's 30 feet.
00:14
Water spreads the area a, although we do as a function of the width s.
00:22
So here we'll have the radius, which would be equals to the arrow, and that's equal to half of the length.
00:32
All right so here let's have the length so the length divided by 2 will be the radius and here we have the width which will simply be the x all right so we can consider the perimeter p which would be equal to we'll have two times the width all right then plus for the purposes of making x as a variable in terms of the area you're going to use instead of the side being the l you're going to say two times the radius which is the diameter and the perimeter actually covers the side that side which is the diameter and also the side then the semicircular side which would be the circumference of a semicircle so here we have two pi are divided by two because you are looking at a semicircle so we have the perimeter p which is equal to 2x plus 2r then plus pi r all right so this is equals to 30.
02:24
So let's call this our first equation.
02:31
And now we are looking at the area.
02:33
So the area we can have two parts.
02:36
All right...