Answer:
147 cm^2
Step-by-step explanation:
To find the surface area, you would have to add up the area of all shapes:
Area of triangle: 1/2 base*height
Area of square: length*width
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square = l*w = 7*7 = 49 cm^2
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So since there are 4 triangles, you would have to multiply the result by 4.
triangle = 1/2 7*9 = 49/2 = 24.5
4 triangles = area of 1 triangle * 4 = 4(24.5) = 98 cm^2
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add them up, and you get 49 + 98 = 147 cm^2
