According to my book:
E(sub 7) = ker(A - 7I(sub 2)) = {v[IMG]file:///C:/Users/Geoffrey/AppData/Local/Temp/moz-screenshot.png[/IMG]in R^2 : Av = 7v}
7 is an eigenvalue and, to me, the question is asking to find matrices A such that Av = 7v. How would I go about this?