## Answers

sum of the three sides is perimeter

area=1/2 base*height

__There are 3 ways to find the perimeter of a triangle -__

**1.Add the lengths of all three sides together to find the perimeter.**

**2.For a right (90º) triangle with two known side lengths:**** Label the longest side c and the other two a and b.****Find the right triangle's third side using the Pythagorean Theorem: a² + b² = c².**

**3.For a triangle with two known side lengths and a known angle between them:****Label the known angle D and the adjacent sides a and b. Label the unknown side c. Find the length of side c using the Law of Cosines: c² = a² + b² - 2ab****cos****(D). **

__For area we have got two ways-__

**1. When base and height are know:****area = 1/2 X b X h ( b = base; h = height )**

**2. When all 3 sides are known:name all 3 sides as a,b and c respectively. s = a+b+c/2.**

**area = √ s (s-a)(s-b)(s-c).**

**There are two other formulas for finding area which are trigonometry based.**