What is the extraneous solution (undefined) to the equation

Secant be and cf intersect at point d inside a what is the measure of cde

Will mark ! (10 points also! ) if x varies inversely with y and x =6 when y= 10, find y when x=8 a. y=4.8 b. y=7.5 c. y=40/3 d. y=4/15

Which is the value of this expression when p=3 and q=-9