Respuesta :

Answer: 175 cm²

Step-by-step explanation:

     Since there are four congruent triangles, we will find the area of one and multiply by 4:

A = [tex]\frac{B*H}{2}[/tex]

A = [tex]\frac{7*9}{2}[/tex]

A = 31.5 cm²

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31.5 cm² * 4 = 126 cm²

     Now, we will find the area of the center square:

A = L²

A = 7²

A = 49 cm²

    Lastly, we will find the total surface area:

126 cm² + 49 cm² = 175 cm²

           The surface area of this square pyramid is 175 cm.