06 Kunci Jawaban dan Pembahasan MAT IX
06 Kunci Jawaban dan Pembahasan MAT IX
06 Kunci Jawaban dan Pembahasan MAT IX
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
5. <strong>Jawaban</strong>: a<br />
(23 ) 2 – ((–2) 3 ) 2 = 23 × 2 – (–2)<br />
= 26 – 26 = 0<br />
6. <strong>Jawaban</strong>: d<br />
0,0001080 = 1,08 × 10 –4<br />
3 × 2<br />
7. <strong>Jawaban</strong>: b<br />
Pembulatan sampai dua tempat desimal:<br />
4.450.000.000 = 4,45 × 10 9<br />
Pembulatan sampai satu tempat desimal:<br />
4.450.000.000 = 4,5 × 10 9<br />
8. <strong>Jawaban</strong>: b<br />
(5 × 10 –5 ) × (4 × 10 –4 ) × 1012 = 5 × 10 –5 × 4 × 10 –4 × 1012 = 5 × 4 × 10 –5 × 10 –4 × 1012 = 20 × 10 –5 – 4 + 12<br />
= 20 × 103 = 2 × 101 + 3 = 2 × 104 9. <strong>Jawaban</strong>: a<br />
(32 ) –4 1<br />
× 3<br />
9 − = 9 –4 1<br />
× 3<br />
9 −<br />
= 9 –4 – (–3)<br />
= 9 –4 + 3<br />
= 9 –1 = 1<br />
9<br />
10. <strong>Jawaban</strong>: d<br />
−5<br />
3<br />
−5<br />
⎛3⎞ ⎛9⎞ 3 3<br />
⎜<br />
4<br />
⎟ × ⎜<br />
⎝ ⎠ 4<br />
⎟ = × − 5 ⎜<br />
⎝ ⎠ 4<br />
⎜ ⎟<br />
4 ⎟<br />
⎝ ⎠<br />
−5<br />
6<br />
3 3<br />
= − 5 × 3<br />
4 4 =<br />
6−5 3<br />
3−5 4<br />
3<br />
= 2<br />
4 − =3 × 42 = 3 × 16 = 48<br />
11. <strong>Jawaban</strong>: a<br />
(32 –3 ) 4 = 2a ⇔ ((25 ) –3 ) 4 = 2a ⇔ 25 × (–3) × 4 = 2a ⇔ 2 –60 = 2a Sehingga, a = –60<br />
Jadi, nilai a = –60.<br />
12. <strong>Jawaban</strong>: c<br />
1<br />
2 5<br />
(3 ) =<br />
−n<br />
⎛1⎞ ⎜<br />
9<br />
⎟<br />
⎝ ⎠<br />
⇔<br />
1<br />
10<br />
3<br />
1<br />
= 2 n<br />
(3 ) −<br />
⇔<br />
1<br />
10<br />
3<br />
1<br />
= 2n<br />
3 −<br />
⇔ 310 = 3 –2n<br />
Sehingga, 10 = –2n<br />
⇔ n = –5<br />
Jadi, nilai 1<br />
n<br />
= – 1<br />
5 .<br />
3<br />
⎛ 2 ⎞<br />
68 <strong>Kunci</strong> <strong>Jawaban</strong> <strong>dan</strong> <strong>Pembahasan</strong> PR Matematika Kelas <strong>IX</strong><br />
13. <strong>Jawaban</strong>: b<br />
(–27) 2z + 6 = 912 – z<br />
⇔ ((–3) 3 ) 2z + 6 = ((–3) 2 ) 12 – z<br />
⇔ (–3) 6z + 18 = (–3) 24 – 2z<br />
Sehingga, 6z + 18 = 24 – 2z<br />
⇔ 8z = 6<br />
⇔ z= 6<br />
8<br />
Jadi, nilai z = 3<br />
4 .<br />
14. <strong>Jawaban</strong>: b<br />
3<br />
x= 164<br />
3<br />
4 = (2 ) 4 = 23 = 8<br />
y=<br />
=<br />
2<br />
3<br />
27<br />
2<br />
3 3<br />
(3 )<br />
= 3 2<br />
2<br />
5<br />
125 :<br />
3<br />
5<br />
25 =<br />
2<br />
3 5<br />
(5 ) :<br />
= 3<br />
4<br />
= 9<br />
Jadi, nilai x – y = 8 – 9 = –1.<br />
15. <strong>Jawaban</strong>: a<br />
3<br />
2 (5 ) 5<br />
=<br />
6<br />
5<br />
5 :<br />
6 6<br />
5 5<br />
5 −<br />
6<br />
5<br />
5<br />
=<br />
= 50 =1<br />
16. <strong>Jawaban</strong>: b<br />
3 3 1<br />
2 4 2<br />
3 3 1<br />
2 2 4 3 2<br />
2(4+ 8) = 2((2) + (2))<br />
17. <strong>Jawaban</strong>: b<br />
1<br />
5 10<br />
=<br />
3 3 3<br />
2 2 2<br />
2(2+ 2)<br />
3 3 3 3<br />
+ +<br />
2 2 2 2<br />
= 2 + 2<br />
= 23 + 23 = 8 + 8<br />
= 16<br />
= 24 − 2<br />
(25 ) + (9 4)<br />
− × (36 6)<br />
=<br />
=<br />
1<br />
25 2<br />
−<br />
1<br />
2 (5 ) 2<br />
−<br />
+<br />
+<br />
1<br />
1<br />
9 2<br />
−<br />
×<br />
1<br />
2 2<br />
(3 ) −<br />
= 5 –1 + 3 –1 × 6<br />
= 1<br />
5<br />
= 1<br />
5<br />
= 2 1<br />
5<br />
+ 1<br />
3<br />
+ 2<br />
× 6<br />
1<br />
2<br />
36<br />
×<br />
1<br />
3<br />
1<br />
2 2<br />
(6 )