Question

Tolong di bantuin ya no 9 sampai 15 sekali gus jalannya


#MB

Answer 1

Verified answer

10.
PS² = RS x SQ
       = RS x (QR - RS)
       = 9 x (34 - 9)
       = 9 x 25
       = 225
PS = √225
PS = 15 cm

Luas segitiga = 1/2 x QR x PS
L = 1/2 x 34 x 15
L = 17 x 15
L = 255 cm² (D)

11.
RN : RQ = 2 : 5
maka
RN : NQ = 2 : 3

MN = (PQ x RN + SR x NQ) / RQ
MN = (25 x 2 + 10 x 3) / 5
MN = (50 + 30) / 5
MN = 80 / 5
MN = 16 cm (B)

12.
DC : CB = 2 : 3
maka
DB = 2 + 3 = 5

FC = (AB x DC + ED x BC)/ DB
12 = (AB x 2 + 8 x 3) / 5
12 x 5 = 2AB + 24
60 = 2AB + 24
2AB = 60 - 24
2AB = 36
AB = 18 cm

AB - DE = 18 cm - 8 cm = 10 cm (C)

13.
t / 160 = 3,2 / 4
t / 160 = 4/5
t = 4/5 x 160
t = 128 cm (B)

14.
ukuran foto
alas = 32 cm
tinggi = 40 cm

ukuran bingkai
lebar = 32 + 4 + 4 = 32 + 8 = 40 cm
panjang = p

p / 40 = 40 / 32
p / 40 = 5/4
p = 5/4 x 40
p = 50 cm

misal lebar bagian bawah bingkai = L
2L = panjang bingkai - tinggi foto
2L = 50 - 40
2L = 10
L = 5 cm (B)

15.
BC = AB = 10 cm
AC² = AB² + BC²
AC² = 10² + 10²
AC² = 100 + 100
AC² = 200
AC = √200
AC = 10√2

BD / AD = BC / AC
BD / (10 - BD) = 10 / 10√2
10√2 BD = 10(10 - BD)
10√2 BD = 100 - 10 BD
10√2 BD + 10 BD = 100
BD(10√2 + 10) = 100
BD = 100 / (10√2 + 10)
BD = 100 / [10(√2 + 1)]
BD = 10 / (√2 + 1)
BD = 10(√2 - 1) / (2 - 1)
BD = (10√2 - 10) cm (B)