please help me fast and show all your work please thx
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Answer:
429 sq. cm
Explanation:
the formula for a triangle is a = 1/2 bh, so each triangle would equal 77. there's 4 triangles so multiply 77 by 4, which is 308. the area of the square below would be 11×11 which is 121, so 121+308 would be 429 sq. cm