How to find the area of the base of a cone

The parabola x= √y-9 opens: a.)up b.)down c.)right d.)left

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¯¯¯¯¯¯¯¯)?

If you are trying to move an attached term across the equal sign (=), what operation would you use to move it?