Problem $7\mathrm{.}5-6$

A cast$-$iron plate in biaxial stress is subjected to tensile stresses ${}_x=31$MPa and ${}_y=17$MPa. The corresponding strains in the plate are ${}_x=240{10}^{-6}$ and ${}_y=85{10}^{-6}.$ Determine Poisson's ratio $v$ and the modulus of elasticity for the material.

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