Page 85 - Matematika-BS-KLS-VII-Licensi
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Soal 3 Sederhanakanlah.
1 6x × 2 2 (-7) × 2y 3 -3a × 4
2
4 -b × (-9) 5 10 × 0,8x 6 a × 6
3
Contoh 4 Sederhanakanlah 2(x + 4).
Ulasan
Cara hapus tanda kurung dengan menerapkan sifat BAB 2
a(b + c) = ab + ac
distributif. b + c │
Penyelesaian a ab ac Aljabar
2(x + 4)
= 2 × x + 2 × 4 b c
= 2x + 8 Jawab: 2x + 8
Contoh 5 1 (2x + 5) × (-3) Ulasan
= 2x × (-3) + 5 × (-3)
(b + c)a = ab + ac
= -6x – 15
Kelas VII Hlm. 92, 127
2 -(7x – 8)
= (-1) × (7x – 8)
= (-1) × 7x + (-1) × (-8)
= -7x + 8
Soal 4 Sederhanakanlah.
1 5(x + 2) 2 -2(4x + 5) 3 (1 – 6x) × 3
2
4 (a – 4) × (-6) 5 -(-9x + 8) 6 (9y + 6)
3
x – 5
x – 5 × 6
Contoh 6 × 6 = 2 (x – 5) × 6
2
= (x – 5) × 3 2 = (x – 5) × 3
=3x – 15
Soal 5 Sederhanakanlah.
3x + 1 x – 3
1 × 4 2 12 ×
2 4
Bab 2 Aljabar 79