00:01
And question that in, we have quadrilateral luck inscribed in the circle of the center s, and the measure of angle luc is 96 degrees and the measure of angle uck is 77 degrees.
00:16
We're going to be finding the measure of angle ulk, ulk.
00:22
So the measure of ulk.
00:25
Now in this quadrilateral luk is a cyclic quadrilateral and in a cyclic got your retinal, opposite sides are supplementary.
00:36
Opposite angles are supplementary meaning that 77 plus the measure of angle l equals 180.
00:44
So to get the measure of angle l, we take 180 minus 77 degrees and so that will be 103 degrees.
00:54
So the correct answer is d.
00:59
In question 14, we're told that among you say i cut a circular board with the diameter of 80 centimeters.
01:09
Then he divided the board into 20 congruent sectors.
01:12
What is the area of each sector? so first we get the area of the full board, which is given by pi r square.
01:19
And we can take it to be, okay, so in terms of pi, it's going to be pi times r squared.
01:26
So the diameter is 80, therefore the radius is 40 squared.
01:30
So this is 16, 1 ,600 pi.
01:35
The area is 100600 pi square centimeters.
01:40
Okay, but it has to be cut into 20 congruent sectors.
01:46
So we divide 1 ,600 pi by 20 so that we get the value of the area of one sector.
01:56
So, and this results into 80 pi square centimeters.
02:01
So the correct answer is, in cursion 15, mary designed a pendant and it is a regular octagon set in a circle.
02:14
And suppose the opposite vertices are connected to the line segments, bit at the center of the circle, what is the measure of which angle formed at the center.
02:25
So we need to sketch this.
02:27
Mary designed a pendant.
02:31
It's a regular octagon set in a circle.
02:36
So we have a circle and then it's a regular octagon.
02:48
And so with an octagon there are eight sides.
02:57
So what we could do is to just draw some lines.
03:05
Split this such that we have eight sides.
03:12
One, two, three...