Answer:
[tex]A_{total} = 295\ cm^2[/tex]
Step-by-step explanation:
Step 1: Determine the area of the bottom rectangle
[tex]A = l * w[/tex]
[tex]A = 20\ cm * 10\ cm[/tex]
[tex]A = 200\ cm^2[/tex]
Step 2: Determine the area of the top rectangle
[tex]A = l * w[/tex]
[tex]A = (20\ cm - 5\ cm - 5\ cm) * (7\ cm)[/tex]
[tex]A = 10\ cm * 7\ cm[/tex]
[tex]A = 70\ cm^2[/tex]
Step 3: Determine the area of the triangles
[tex]A = \frac{h * b}{2}[/tex]
[tex]A=\frac{(22\ cm - 10\ cm - 7\ cm)*(\frac{20\ cm - 5\ cm - 5\ cm}{2})}{2}[/tex]
[tex]A=\frac{5\ cm * 5\ cm}{2}[/tex]
[tex]A = 12.5\ cm^2[/tex]
Since we have found the area of one right triangle we need to multiply by 2 to get the area for both of the triangles.
[tex]A = 12.5\ cm^2*2[/tex]
[tex]A = 25\ cm^2[/tex]
Step 4: Determine the total area
[tex]A_{total} = 200\ cm^2 + 70\ cm^2 + 25\ cm^2[/tex]
[tex]A_{total} = 295\ cm^2[/tex]
Answer: [tex]A_{total} = 295\ cm^2[/tex]
