The probability of obtaining nine heads in a row when flipping a coin is nothing. (round to five decimal places as needed.)

What are the measures of ∠a, ∠b, ∠c and ∠d? explain how to find each of the angle measure.

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

Which property was used to simplify the expression? 3c+9 +4c=3c+4c+9