Question

Consider x=h(y,z)x=h(y,z) as a parametrized surface in the natural way. Write the equation of the tangent plane to the surface at the point (−1,−5,−1)(−1,−5,−1) given that ∂h∂y(−5,−1)=4∂h∂y(−5,−1)=4 and ∂h∂z(−5,−1)=−2∂h∂z(−5,−1)=−2.