If a point is on the bisector of an angle, then it is

Worth 30 points! in this diagram, both polygons are regular. what is the value, in degrees, of the sum of the measures of angles abc and abd?

What is the point of inflection for the function f(x)=2cos4x on the interval (0, pi/2)

Larry wants to buy some carpeting for his living room. the length of the room is 4 times the width and the total area of the room is 16 square meters. what is the length of the living room