Question

I have been given values of properties of a CFRP material and asked to calculate a number of matrix (transformation etc). I have done this but I am now asked to calculate the stresses and strains in the 1-2 directions.

Please could you help me? I don't know what equation I should use.
I know to calculate the strains in the x-y direction you use the following;
{εxy }= [s ̅ ]{σxy }

Please could you tell me the matrix to use for;
1. the stresses in the 1-2 directions
2. the strains in the 1-2 directions.

Thank you in advance