Which expression is not equal to the expression shown?

Arectangle has an area of 54 square feet. if the length is 3 feet more than the width, find the dimensions of the rectangle.

Given the following statements, which is the best

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¯¯¯¯¯¯¯¯)?