tolang jawab... pliss...

sorry hnya bsa no 1.......

1. 5/12 x 90 = 37 1/2 ( c )
2. a = 3a + 2a + 20 = 180
       = 5a + 20 = 180
       = 5a = 180-20 =160
       = a = 160 : 5 = 32
<abd = 3 x 32 + 20 = 96 + 20 = b. 116

5a dari 3a ditambah 2a

maaf kl slah