If angle ABE is a right angle, it means it measures 90 degrees. According to the given information, the measure of angle ABE is 3x + 6. Setting this equal to 90 degrees gives us the equation:
3x + 6 = 90
Now we can solve for x:
3x = 90 - 6
3x = 84
x = 84 / 3
x = 28
So, the value of x is 28.