Perbandingan p:l:t sebuah balok adalah 5:3:2.jika volume balok tersebut adalah 810 cm3.Maka luas permukaan balok tersebut adalah... a. 240 cm2 b. 480 cm2 c. 558 cm2 d. 738 cm2 Tolong jelasin caranya yang jelas ya :)
salmanulinnuha
V = pxlxt 810 = (5x) x (3x) x (2x) 810 = 30x³ 810/30 = x³ 27 = x³ √27 = x 3 = x panjang p, l, dan t p = 5x = 5(3) = 15 l = 3x = 3(3) = 9 t = 2x = 2(3) = 6 L Permukaan 2x (p.l + p.t + l.t) 2x (15.9 + 15.6 + 9.6) 2x (135 + 90 + 54) 2x 279 558cm²
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liwonsubagyo
Perbandingan = p : l : t = 5 : 3 : 2 Volume balok = p x l x t 810 = 5x x3x x 2x 810 = 30x 30x = 810 x = 27 27 : 3 = 9 Panjang = 5/9 x 27 = 15cm lebar = 3/9 x 27 = 9cm tinggi = 2/9 x 27 = 6 cm Lp = 2 ( pl + pt + lt ) = 2 ( 15x 9 + 15 x 6 + 9 x 6 ) = 2 ( 135 + 90 + 54 ) = 2 x 297 = 558cm² Jawaban ( C )
810 = (5x) x (3x) x (2x)
810 = 30x³
810/30 = x³
27 = x³
√27 = x
3 = x
panjang p, l, dan t
p = 5x
= 5(3)
= 15
l = 3x
= 3(3)
= 9
t = 2x
= 2(3)
= 6
L Permukaan
2x (p.l + p.t + l.t)
2x (15.9 + 15.6 + 9.6)
2x (135 + 90 + 54)
2x 279
558cm²
Volume balok = p x l x t
810 = 5x x3x x 2x
810 = 30x
30x = 810
x = 27
27 : 3 = 9
Panjang = 5/9 x 27 = 15cm
lebar = 3/9 x 27 = 9cm
tinggi = 2/9 x 27 = 6 cm
Lp = 2 ( pl + pt + lt )
= 2 ( 15x 9 + 15 x 6 + 9 x 6 )
= 2 ( 135 + 90 + 54 )
= 2 x 297
= 558cm²
Jawaban ( C )