Tolong kak itu soal persamaan nilai mutlak

Tolong kak itu soal persamaan nilai mutlak

64.

–3| x – 7 | + | x – 3 | = 0

| x – 3 | = 3| x – 7 |

» Untuk (x – 3) = –[3(x – 7)]

x – 3 = –3x + 21

x + 3x = 21 + 3

4x = 24

x = 6

» Untuk (x – 3) = +[3(x – 7)]

x – 3 = 3x – 21

x – 3x = –21 + 3

–2x = –18

x = 9

Jadi, x = 6 atau x = 9

65.

$frac{1}{2} x + 3 : | : frac{1}{2}x + 1 : | = frac{1}{4}$

$3 : | : frac{1}{2}x + 1 : | = frac{1}{4} - frac{1}{2} x$

$| : frac{1}{2}x + 1 : | = frac{1}{12} - frac{1}{6} x$

$Untuk : (frac{1}{2}x + 1) = - ( frac{1}{12} - frac{1}{6} x )$

$frac{1}{2}x + 1 = - frac{1}{12} + frac{1}{6} x$

$frac{1}{2}x - frac{1}{6} x = - frac{1}{12} - 1$

$frac{1}{3} x = - frac{13}{12}$

$x = - frac{39}{12} = - frac{13}{4}$

$Untuk : (frac{1}{2}x + 1) = + ( frac{1}{12} - frac{1}{6} x )$

$frac{1}{2}x + 1 = frac{1}{12} - frac{1}{6} x$

$frac{1}{2}x + frac{1}{6} x = frac{1}{12} - 1$

$frac{2}{3} x = - frac{11}{12}$

$x = - frac{11}{8}$

$boxed{Jadi, : x = - frac{13}{4} : : atau : : x = - frac{11}{8}}$