What is the length of AB?

A.12
B.9
C.6
D.3

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.

28

step-by-step explanation:

because that's the answer