How can nationalism lead to imperialism?

Nationalism can basically be defined as the idea that your country is superior to all others. Also if people feel nationalistic, well they might start wanting to prove that their country is better than others. So basically one way to prove this is by taking an empire. Also nationalism is a belief that one's country is the best. Imperialism allows a nation to just expand it's borders and to gain more valuable raw materials and trade markets. Nationalists just believed that their nation's values were just the best and that these had to be spread to the developing world.

the perimeter of a triangle is 69 cm. side a is 5 cm shorter than side b. side c is twice as long as side a. find the length of each side. i need to know how to do it in 2 equations.  

equations:

a = b-5

c = 2a

a + b + c = 69

beowulf is considered an epic poem because it describes the actions of a great warrior.

beowulf is taken into account an epos. in this poem, the main character may be a hero who travels nice distances to prove his strength at not possible odds against supernatural demons and beasts. in the poem, beowulf was a young warrior and he leaves his country to hrothgar, as hrothgar was in a great trouble.