Find the exact value of the expression 1 + cot^2(30°) - sec^2(45°)

Jack has a piece of red ribbon that is two times as long as his piece of blue ribbon. he says that he can use two different equation to find out how long his piece of red ribbon is compared to his piece of blue ribbon is. is he correct? explain his reasoning

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?

Cole says the distance between points (-5,0) and (0,-5)is 5 units. is he correct? explain why or why not.