Question 252878
the graphs of these two equations is shown below:


{{{graph (600,600,-5,5,-5,5,3,sqrt(16-x^2),-sqrt(16-x^2))}}}


looks like there are 2 points of intersection.


you could solve for these by taking the equation of x^2 + y^2 = 16 and substituting 3 for y and then solving for x.


x^2 + y^2 = 16 becomes:


x^2 + (3)^2 = 16 becomes:


x^2 + 9 = 16 becomes:


x^2 = 16-9 = 7 becomes:


x = +/- sqrt(7) which is roughly 2.65 (more accurately shown as 2.645751311).


you can see on the graph that y = 3 intersection points roughly correspond to x = +/- 2.65.