Hi, trying to figure out this question, made a guess at how to do it but ended up with the wrong answer .

A =

[x -4]

[y 2]

I need to find the x and y where A^2 = A.

I tried figuring out A^2 and got:

[x²-4y -4x-8]

[xy+2y -4y+4]

I set that equal to the original A and took the resulting equations:

x² - 4y - 4x - 8 = x - 4

xy + 2y - 4y + 4 = y + 2

And rearranged/substituted and ended with:

x = 1

y = -2

Unfortunately it seems that wasn't the correct answer. So at this point I'm not really sure how to solve this question, can anyone help with this?

Thanks!