Step 1
Given;
[tex]\begin{gathered} cosE=sinF \\ measure\text{ of angle E=26}^o \end{gathered}[/tex]Required; To find the measure of angle F
Step 2
[tex]\begin{gathered} cos26=sinF \\ \sin\left(90^{\circ\:}-26^{\circ\:}\right)=cos26 \end{gathered}[/tex][tex]\begin{gathered} \sin\lparen F)=\sin\left(90^{\circ\:}-26^{\circ\:}\right) \\ sin(F)=sin(64) \end{gathered}[/tex]Answer;
[tex]m\angle F=64[/tex]