The correct answer would be that Carl is 4 years old. If John is 20 years older than Carl, that would make him 24. 24 + 4 = 28 years. Therefore, Carl must be 4 years old.
The four transformations:
Translation, Rotation, Reflection, and Scaling
Each of these transformations change how or where the shape is. Each of these transformations change the shape or shapes in different ways. Dilations change the size and sometimes even the shape of the shape; translation, rotation, and reflection just move the shape around they don't change the size or shape of it.
Is that what you are looking for? Let me know if there anything more...
B2-7b+12=0
(b-3)(b-4)=0
b= 3 or 4