Cos 210° = cos ( 180° + 30° ) - cos 30° = - √3/2
A circumscribed angle is that which is formed by the intersection of the two tangent lines in a circle. With this, we can conclude that segments AC and AB are tangent to circle O. The tangent lines forms a right angle with the radius of the circle drawn from the center of the circle to the tangent point.
By the explanation above, we can say that angles C and B are equal to 90° and that triangle ACO and triangle ABO are congruent. Which means that segment AC is equal to segment AB. Thus, the length of AB is also 4.
<em>Answer: 4 units</em>
Hmm idk if this is what you need, but here we go: Amy is 5 years older than her brother, John. Her age is 19. How old is John?
x-John
x+5=19
x=19-5=14
John is 14.
Using Pythagoras Theorem,
(b is the length of the ladder from the ground)
11x11=6x6+(b^2)
121-36=(b^2)
85=(b^2)
b= 9.219544457292887
b is approximately 9.2