9n=126, how do you solve this problem?

Which undefined geometric term is described as a location on a coordinate plane that is designed by an ordered pair (x,y) ?

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¯¯¯¯¯¯¯¯)?

Graph the equationy=x^2 -[tex]y = x^{2} - 2[/tex]