Given,

ABCD & AEFG are two parallelograms

∠C = 58°

∵ AB││CD , AE││FG ,BC││AD , EF││AG

GF produced to H so GH││AB

= ∠C = ∠H (corresponding angles)

= ∠H = 58°

AD││BC and GH cuts them

Hence , ∠F = ∠H (corresponding angles)

∠F = 58°.