What is the length of JM

Two sides of a triangle mesure 20cm and 30cm. what is the measure of the third side

Atriangular bandana has an area of 46 square inches. the height of the triangle is 5 3 4 inches. enter and solve an equation to find the length of the base of the triangle. use b to represent the length of the base.

Find the measure of the interior angles of the following regular polygons: a triangle, a quadrilateral, a pentagon, an octagon, a decagon, a 30-gon, a 50-gon, and a 100-gon.