MEI OCR C1 help

Could someone please post up the worked solutions to questions 13 ii and 13 iii?

Cheers

(the link to the pdf is:http://www.ocr.org.uk/Images/58613-question-paper-unit-4751-introduction-to-advanced-mathematics.pdf)

i) You need to know that the equation of a circle with centre (a,b) and radius r is $(x-a)^2+(y-b)^2=r^2$.

ii) The y coordinates of the required points are 0. Substitute y=0 in the given equation and solve to find x.

iii) Substitute the given values in the equation and simplify.

Cheers - but how do I find the equations of the tangents?

Could someone please post up the worked solutions to questions 13 ii and 13 iii?

Cheers

(the link to the pdf is:http://www.ocr.org.uk/Images/58613-question-paper-unit-4751-introduction-to-advanced-mathematics.pdf)