What is 10-5/2 and how do i do the math

Combined megan and kelly worked 60 hours.kelly worked twice as many hours as megan.how many hours did they each worked?

Which graph represents the following piecewise defined function?

With this question substitute t=3 and t=5 to determine if the two expressions are equivalent. 4(t + 3) 4t+12 which statements are true? check all that apply. a. the value of both expressions when t =5 is 32. b. the two expressions are not equivalent. c. the value of both expressions when t=3 is 15. d. the value of both expressions when t=5 is 23. e. the two expressions are equivalent. f. the value of both expressions when t=3 is 24.