4 + 5x-x + 19 simplify expressions using like terms

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¯¯¯¯¯¯¯¯)?

Create a data set with 8 points in it that has a mean of approximately 10 and a standard deviation of approximately 1.

Need solving this 2nd limit problem.