We see that the sign is a triangle and the area of a triangle is given by the expression:
[tex]A=\frac{1}{2}\text{base}\times height[/tex]base=36
height=32
Then,
[tex]\begin{gathered} A=\frac{1}{2}36\times32 \\ A=\frac{1152}{2}=576\text{ square inches} \end{gathered}[/tex]