Kak tolong bantu kak
19]
4x^2 – 64 = 0
(2x + 8)(2x – 8) = 0
2x + 8 = 0 atau 2x – 8 = 0
2x = -8 atau 2x = 8
x = -8/2 atau x = 8/2
x = -4 atau x = 4
HPnya adalah {4 , -4} (A)
22]
K = 68 m
L = 240 m^2
K = 2 × (p + l)
68 = 2 × (p + l)
p + l = 68/2
p + l = 34
L = p × l
240 = p × l
p = 240/l
p + l = 34
240/l + (l^2)/l = 34
(240 + l^2)/l = 34
l^2 + 240 = 34 × l
l^2 + 240 = 34l
l^2 – 34l + 240 = 0
(l – 24)(l – 10) = 0
l – 24 = 0 atau l – 10 = 0
l = 24 atau l = 10
l = 24 tidak memenuhi karena lebih panjang dari 10 , maka l = 10 m
p = 240/l
p = 240/10
p = 24 m
d = V(p^2 + l^2)
d = V(24^2 + 10^2)
d = V(576 + 100)
d = V676
d = 26 m (C)
6]
(3^-4 × 2^-3)/(2^-5 × 3^-2)
= (2^5 × 3^2)/(2^3 × 3^4)
= 2^(5-3) × 3^(2-4)
= 2^2 × 3^-2
= (2^2)/(3^2) (B)