Option A:
The length of AB is 12.
Solution:
Given ABC is a triangle.
∠A = 50° and ∠B = 50°
AB = 4x and BC = 2x + 6
To find the length of AB:
∠A = 50° and ∠B = 50°
So, ∠A = ∠B
In triangle, sides opposite to equal angles are equal.
⇒ AB = BC
⇒ 4x = 2x + 6
Subtract 2x from both sides.
⇒ 2x = 6
Divide by 2 on both sides.
⇒ x = 3
AB = 4x
= 4 × 3
= 12
AB = 12
Hence option A is the correct answer.
The length of AB is 12.
