Tentukan volume dan luas permukaan bangun ruang di atas.

Pertanyaan

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Pembahasan Soal:

Misalkan tinggi segitiga sisi limas adalah $begin mathsize 14px style x. end style$

$begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row straight x equals cell square root of 6 squared plus 15 squared end root end cell row blank equals cell square root of 36 plus 225 end root end cell row blank equals cell square root of 261 end cell row blank equals cell 3 square root of 29 space cm end cell row cell Luas space permukaan end cell equals cell 5 cross times sisi space persegi plus 4 cross times segitiga space limas end cell row blank equals cell 5 cross times 12 squared plus 4 cross times fraction numerator 12 cross times 3 square root of 29 over denominator 2 end fraction end cell row blank equals cell left parenthesis 720 plus 72 square root of 29 space right parenthesis space cm squared end cell row cell Volume space total end cell equals cell Volume space Limas plus Volume space kubus end cell row blank equals cell 1 third cross times 12 squared cross times 15 plus 12 cubed end cell row blank equals cell 720 plus 1.728 end cell row blank equals cell 2.448 space cm cubed. end cell end table end style$

Jadi, luas permukaan bagun ruang di atas adalah $begin mathsize 14px style left parenthesis 720 plus 72 square root of 29 right parenthesis space cm squared end style$ dan volumenya $begin mathsize 14px style 2.448 space cm cubed. end style$

Pembahasan terverifikasi oleh Roboguru

Terakhir diupdate 12 Maret 2021