Help needed:).

What is the effect on the graph of the parent function f(x) = x when f(x) is replaced with 3f(x)? a) shifts the line 3 units up b) shifts the line 3 units down c) increases the slope of the line by a factor of 3 d) decreases the slope of the line by a factor of 3

Given that ot =5, xt=12, and ox= 13 is xy tangent to circle o at t? explain.

Can someone tell me if this is perpendicular? !