## Introduction to Euclid Geometry

**Chapter 5**

**Exercise 5.2**

**EX 5.2 QUESTION 1.**

**How would you rewrite Euclid’s fifth postulate so that it would be easier to understand?**

**Solution:**

If two lines intersect the third line in such a way that the sum of the interior angles is less than 180°, then the two lines intersect each other.

**EX 5.2 QUESTION 2.**

**Does Euclid’s fifth postulate imply the existence of parallel lines ? Explain.**

**Solution:**

Yes, Euclid’s fifth postulate does imply the existence of the parallel lines. Because if two lines intersect the third line in such a way that the sum of the interior angles is less than 180°, then the two lines intersect each other but if the sum of interior angles is 180°, then the lines don’t intersect or line are parallel.