What is the value of x? Rounded to the nearest tenth.

Hannah is 3 years older than twice her brother joey’s age. joey is 2 years old. how old is hannah? show all of your work! the number of students is five more than seven times the number of teachers. there are 10 teachers. how many students are there? be sure to show all of your work!

List the elements of the set in roster notation. (enter empty or ∅ for the empty set.) {x | x is a letter in the word hippopotamus}

Arley is building a model of a city map. in one part of the city, three roads form a right triangle, which harley draws as triangle abc, with the following measures: m∠b=90° and m∠a=30°. in his scale model, the hypotenuse of triangle abc, ac¯¯¯¯¯¯¯¯, has a length of 817−−√ cm. what is the value of a (the length of bc¯¯¯¯¯¯¯¯)?