Find the length of AB

AB is 15

Step-by-step explanation:

AB and BC are equal because the line that goes through the triangle is going through at a 90 degree angle, u can see that by the small square, and u know it's in the middle bc of the short lines on AD and DC, the short lines means that they are congruent, so:

5x = 4x + 3

subtract 4x from both sides

x = 3

Now u have x, put it in the equation

5x = 5(3) = 15

4x and 6y

im not sure though