Please help me on 7 & 10

The sum of two numbers is 58. the first number is 8 less than half the second number. let  c  represent the first number. let  drepresent the second number. which statements about solving for the two numbers are true? check all that apply.the equation    represents the sum of the two numbers.the equation    represents the sentence “the first number is 8 less than half the second number.”the equation    represents the relationship between the two numbers.the equation    represents the sum of the two numbers.the number  d  is 14.the number  c  is 44.the number  c  is 14.the number  d  is 44.

Don't know how to find x given these segment lengths

Ascientist places 24 cells in a petri dish. she knows the cells grow at an exponential rate, doubling in number every hour. how long will it take (in hours) for there to be 1100 cells in the dish? time to 1100 cells: 5.51832530 hours how long will it take to reach 110 cells? time to 110 cells : 2.1963972 hours what is the average rate of change in the number of cells between 9 hours and 11 hours? average rate of change: cells per hour what is the instantaneous rate of change after 7 hours? instantaneous rate of change: cells per hour note: you can earn partial credit on this problem.