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In triangle ABC, angle C is equal to 90 degrees and angle ABC is equal to 30 degrees. Segment AL is an angle bisector and CL is equal to 6 ft. What is the length of segment LB?

User Azangru
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Final answer:

The length of segment LB in triangle ABC, where angle C is 90 degrees, angle ABC is 30 degrees, and segment CL is 6 ft long, is 6√3 feet as it's a 30-60-90 triangle.

Step-by-step explanation:

The student is asking about a geometry problem involving a right triangle, triangle ABC, with a known 90-degree angle at C and a 30-degree angle at ABC.

The problem involves finding the length of segment LB when the angle bisector AL divides the 30-degree angle ABC into two 15-degree angles, and the length of segment CL is given as 6 ft.

Since angle ABC is 30 degrees, when divided by the bisector AL, we get two angles of 15 degrees each. Triangle ACL will then have angles of 90, 15, and 75 degrees.

Using the fact that the sum of the angles in any triangle is 180 degrees, we know that angle ALB is 75 degrees since it is supplementary to the 15 degree angle CAL. Hence, triangle ABL is a 30-60-90 triangle, where angle ALB is 60 degrees and angle ABL is 30 degrees

Now, in a 30-60-90 triangle, the lengths of the sides are in the ratio 1:√3:2.

Since CL is the side opposite the 30-degree angle, and its length is 6 ft, LB, which is opposite the 60-degree angle, would be 6√3 feet long.

We can use the Pythagorean theorem or knowledge of special triangles to arrive at this conclusion.

User Laurynas Biveinis
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