Question

Find parametric equations for the rectangular equation x2 + y2 = 16.

Answer 1

this is an equation of a circle with radius 4, centered (0,0)
so we can make parametric equations. use the parameter theta , you can think of a unit circle, every theta determines a point (x,y) on the circle) . x = 4 cos theta, y = 4 sin theta. , or you can write t instead of theta. but theta is the 'parameter'