A triangle has a perimeter of 55cm, if the sum of two sides is 30cm, find the length of the other side

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.

The moats separating people from the animals are 5 m wide for lions and 4 m wide for the elephants. if the lion’s moat is 4 m deep, how deep should the elephants’ moat be?

]supplementary angles are two angles that add up to . • complementary angles are two angles that add up to degrees. • adjacent angles share a and a • congruent angles have the measure. • an triangle has one angle that is greater than 90 degrees. • a triangle with angles 45°, 45°, and 90° would be a triangle