Recall that the area of a trapezoid is determined by the equation
[tex]\begin{gathered} A=\frac{a+b}{2}\cdot h \\ \text{where} \\ a\text{ and }b\text{ are the bases} \\ h\text{ is the height} \end{gathered}[/tex]
The area of the glass panel therefore should be the area of the trapezoid, minus the two area of the rectangle that has been cutout.
Given that
a = 28 1/4 inches
b = 16 1/4 inches
h = 8 inches
Area of rectangle = 12 3/8 square inches
Then the area of the glass panel is
[tex]\begin{gathered} A=(\frac{a+b}{2}\cdot h)-2\cdot12\frac{3}{8} \\ A=(\frac{28\frac{1}{4}+16\frac{1}{4}}{2}\cdot8)-24\frac{3}{4} \\ A=(44\frac{2}{4}\cdot4)-24\frac{3}{4} \\ A=178-24\frac{3}{4} \\ A=153\frac{1}{4} \end{gathered}[/tex]
Therefore, the area of the glass panel is 153 1/4 square inches.
