jawab no.16 17 18 aja kak...

16) (5a+4) + (7a+8) =180
12a + 12 =180
12a= 180-12
12a=168
a= 168:12
a=14
<cbd
=7a+8
=7 ×14 +8
=106 (b)

17) (3x) + (2x+5) + (25) =180
5x +30=180
5x =180-30
5x = 150
x= 30

<A
2x+5
2×30 +5
65

18) 85

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