Question

25. In the diagram, CT = 10.
What is the length of AB?

Answer 1

I think it’s 5 according to the 30,60,90 degree rule

Answer 2

The length of AB is 4.33012701892

Explanation:

1. You find 10*sin(60 degrees), because sin(60 degrees) = x/CT, and CT = 10. That means that sin(60 degrees) = x/10. You multiply by 10 on both sides, which would mean that x = 10sin(60 degrees) and that AT = 8.66025403784 because x is AT.

2. Then, because the relation between AT and AB and Angle T is sine, you use cosine to find x. If you do that, you find that the equation is sin(30 degrees) = x/8.66025403784. That means that 8.66025403784*sin(30 degrees) = x. If you calculate that, you find that x = 4.33012701892, and AB is x.