If A = x 4

.........y 7

(^^^^ that is a 2x2 matrix)

determine the values of x and y for which A^2=A.

No idea how to start this one.

i didnt think it was possible because

A^2 = x^2 16

..........y^2 49

A = x 4

......y 7

so how can A^2 ever equal A because no matter what the x and y values are, 4 and 7 will never equal 16 and 49?

Help please

Thank you