What is the factored form of the quadratic expression x^2+36

Which of the following graphs could represent a cubic function?

What is the value of x? assume that the line is tangent to the circle.

Taylor graphs the system below on her graphing calculator and decides that f(x)=g(x) at x=0, x=1, and x=3. provide taylor with some feedback that explains which part of her answer is incorrect and why it is incorrect. f(x)= 2x+1 g(x)= 2x^2+1