The thin rectangular plate is subjected to strains of

${\epsilon }_x=+900 \mu m/m$,
${\epsilon }_y=-600 \mu m/m$, and
${\gamma }_{xy}=-850 \mu rad$.

Determine the normal strains ${\epsilon }_n$ and ${\epsilon }_t$ and shear strain ${\gamma }_{nt}$ for $\theta =+{50}^{\circ }$.