Berikut ini adalah pertanyaan dari sihombingfamily443 pada mata pelajaran Matematika untuk jenjang Sekolah Menengah Pertama
![Selesaikan sistem persamaan linear dua variabel berikut dengan metode grafik, substitusi, eliminasi.](https://id-static.z-dn.net/files/d02/3f301fde042992446f472ca38f43e0d3.jpg)
Jawaban dan Penjelasan
Berikut ini adalah pilihan jawaban terbaik dari pertanyaan diatas.
Bagian a
1. Metode Substitusi
x + y = 8 .... (1)
y - x = 2
y = 2 + x.... (2)
- Substitusi pers (2) ke pers (1)
y + x = 8
2 + x + x = 8
2 + 2x = 8
2x = 8 - 2
2x = 6
x = 6/2
x = 3
- Substitusi nilai x ke pers (2)
y = 2 + x
y = 2 + 3
y = 5
Hp = {3, 5}
2. Metode Eliminasi
x + y = 8 .... (1)
y - x = 2
-x + y = 2 .... (2)
- Eliminasi x dari pers (1) dan (2)
x + y = 8
-x + y = 2
_______ +
2y = 10
y = 10/2
y = 5
- Eliminasi y dari pers (1) dan (2)
x + y = 8
-x + y = 2
_______ –
2x = 6
x = 6/2
x = 3
Hp = {3, 5}
3. Metode Grafik
x + y = 8
- Titik potong sumbu x (y = 0)
x + y = 8
x + 0 = 8
x = 8 → tipot = (8, 0)
- Titik potong sumbu y (x = 0)
x + y = 8
0 + y = 8
y = 8 → tipot = (0, 8)
-x + y = 2
- Titik potong sumbu x (y = 0)
-x + y = 2
-x + 0 = 2
x = -2 → tipot = (-2, 0)
- Titik potong sumbu y (x = 0)
-x + y = 2
0 + y = 2
y = 2 → tipot = (0, 2)
Gambar terlampir di slide 1
Bagian b
1. Metode Substitusi
x - 2y = -1
x = 2y - 1 ....(1)
2x + 3y = 12 .... (2)
- Substitusi pers (1) ke pers (2)
2x + 3y = 12
2(2y - 1) + 3y = 12
4y - 2 + 3y = 12
4y + 3y = 12 + 2
7y = 14
y = 14/7
y = 2
- Substitusi nilai y ke pers (1)
x = 2y - 1
x = 2(2) - 1
x = 4 - 1
x = 3
Hp = {3, 2}
2. Metode Eliminasi
- Eliminasi x dari pers (1) dan (2)
x - 2y = -1 | ×2| 2x - 4y = -2
2x + 3y = 12 | ×1| 2x + 3y = 12
__________ –
-7y = -14
y = 2
- Eliminasi y dari pers (1) dan (2)
x - 2y = -1 | ×3| 3x - 6y = -3
2x + 3y = 12 | ×2| 4x + 6y = 24
__________ +
7x = 21
x = 3
Hp = {3, 2}
3. Metode Grafik
x - 2y = -1
- Titik potong sumbu x (y = 0)
x - 2y = -1
x - 2(0) = -1
x - 0 = -1
x = -1 → tipot = (-1, 0)
- Titik potong sumbu y (x = 0)
x - 2y = -1
0 - 2y = -1
y = ½
y = 0,5 → tipot = (0; 0,5)
2x + 3y = 12
- Titik potong sumbu x (y = 0)
2x + 3y = 12
2x + 3(0) = 12
2x = 12
x = 6 → tipot = (6, 0)
- Titik potong sumbu y (x = 0)
2x + 3y = 12
2(0) + 3y = 12
3y = 12
y = 4 → tipot = (0, 4)
Gambar grafik terlampir pada slide kedua
#LearnWithPanda
![Bagian a1. Metode Substitusix + y = 8 .... (1) y - x = 2 y = 2 + x.... (2) Substitusi pers (2) ke pers (1) y + x = 82 + x + x = 8 2 + 2x = 8 2x = 8 - 2 2x = 6 x = 6/2 x = 3Substitusi nilai x ke pers (2)y = 2 + xy = 2 + 3y = 5Hp = {3, 5}2. Metode Eliminasix + y = 8 .... (1) y - x = 2-x + y = 2 .... (2)Eliminasi x dari pers (1) dan (2) x + y = 8-x + y = 2_______ + 2y = 10 y = 10/2 y = 5Eliminasi y dari pers (1) dan (2) x + y = 8-x + y = 2_______ – 2x = 6 x = 6/2 x = 3Hp = {3, 5}3. Metode Grafikx + y = 8Titik potong sumbu x (y = 0) x + y = 8x + 0 = 8 x = 8 → tipot = (8, 0) Titik potong sumbu y (x = 0) x + y = 80 + y = 8 y = 8 → tipot = (0, 8) -x + y = 2Titik potong sumbu x (y = 0) -x + y = 2-x + 0 = 2 x = -2 → tipot = (-2, 0) Titik potong sumbu y (x = 0) -x + y = 2 0 + y = 2 y = 2 → tipot = (0, 2) Gambar terlampir di slide 1Bagian b1. Metode Substitusix - 2y = -1 x = 2y - 1 ....(1)2x + 3y = 12 .... (2)Substitusi pers (1) ke pers (2) 2x + 3y = 122(2y - 1) + 3y = 12 4y - 2 + 3y = 12 4y + 3y = 12 + 2 7y = 14 y = 14/7 y = 2Substitusi nilai y ke pers (1) x = 2y - 1x = 2(2) - 1x = 4 - 1x = 3Hp = {3, 2}2. Metode EliminasiEliminasi x dari pers (1) dan (2) x - 2y = -1 | ×2| 2x - 4y = -22x + 3y = 12 | ×1| 2x + 3y = 12 __________ – -7y = -14 y = 2Eliminasi y dari pers (1) dan (2) x - 2y = -1 | ×3| 3x - 6y = -32x + 3y = 12 | ×2| 4x + 6y = 24 __________ + 7x = 21 x = 3Hp = {3, 2}3. Metode Grafikx - 2y = -1Titik potong sumbu x (y = 0) x - 2y = -1x - 2(0) = -1 x - 0 = -1 x = -1 → tipot = (-1, 0) Titik potong sumbu y (x = 0) x - 2y = -10 - 2y = -1 y = ½ y = 0,5 → tipot = (0; 0,5) 2x + 3y = 12Titik potong sumbu x (y = 0) 2x + 3y = 122x + 3(0) = 12 2x = 12 x = 6 → tipot = (6, 0) Titik potong sumbu y (x = 0) 2x + 3y = 122(0) + 3y = 12 3y = 12 y = 4 → tipot = (0, 4) Gambar grafik terlampir pada slide kedua#LearnWithPanda](https://id-static.z-dn.net/files/d34/8283f118fb40349c27a00aaf86e1c1d6.jpg)
![Bagian a1. Metode Substitusix + y = 8 .... (1) y - x = 2 y = 2 + x.... (2) Substitusi pers (2) ke pers (1) y + x = 82 + x + x = 8 2 + 2x = 8 2x = 8 - 2 2x = 6 x = 6/2 x = 3Substitusi nilai x ke pers (2)y = 2 + xy = 2 + 3y = 5Hp = {3, 5}2. Metode Eliminasix + y = 8 .... (1) y - x = 2-x + y = 2 .... (2)Eliminasi x dari pers (1) dan (2) x + y = 8-x + y = 2_______ + 2y = 10 y = 10/2 y = 5Eliminasi y dari pers (1) dan (2) x + y = 8-x + y = 2_______ – 2x = 6 x = 6/2 x = 3Hp = {3, 5}3. Metode Grafikx + y = 8Titik potong sumbu x (y = 0) x + y = 8x + 0 = 8 x = 8 → tipot = (8, 0) Titik potong sumbu y (x = 0) x + y = 80 + y = 8 y = 8 → tipot = (0, 8) -x + y = 2Titik potong sumbu x (y = 0) -x + y = 2-x + 0 = 2 x = -2 → tipot = (-2, 0) Titik potong sumbu y (x = 0) -x + y = 2 0 + y = 2 y = 2 → tipot = (0, 2) Gambar terlampir di slide 1Bagian b1. Metode Substitusix - 2y = -1 x = 2y - 1 ....(1)2x + 3y = 12 .... (2)Substitusi pers (1) ke pers (2) 2x + 3y = 122(2y - 1) + 3y = 12 4y - 2 + 3y = 12 4y + 3y = 12 + 2 7y = 14 y = 14/7 y = 2Substitusi nilai y ke pers (1) x = 2y - 1x = 2(2) - 1x = 4 - 1x = 3Hp = {3, 2}2. Metode EliminasiEliminasi x dari pers (1) dan (2) x - 2y = -1 | ×2| 2x - 4y = -22x + 3y = 12 | ×1| 2x + 3y = 12 __________ – -7y = -14 y = 2Eliminasi y dari pers (1) dan (2) x - 2y = -1 | ×3| 3x - 6y = -32x + 3y = 12 | ×2| 4x + 6y = 24 __________ + 7x = 21 x = 3Hp = {3, 2}3. Metode Grafikx - 2y = -1Titik potong sumbu x (y = 0) x - 2y = -1x - 2(0) = -1 x - 0 = -1 x = -1 → tipot = (-1, 0) Titik potong sumbu y (x = 0) x - 2y = -10 - 2y = -1 y = ½ y = 0,5 → tipot = (0; 0,5) 2x + 3y = 12Titik potong sumbu x (y = 0) 2x + 3y = 122x + 3(0) = 12 2x = 12 x = 6 → tipot = (6, 0) Titik potong sumbu y (x = 0) 2x + 3y = 122(0) + 3y = 12 3y = 12 y = 4 → tipot = (0, 4) Gambar grafik terlampir pada slide kedua#LearnWithPanda](https://id-static.z-dn.net/files/d30/9e2378761f5100868a36bd9fffc838f7.jpg)
![Bagian a1. Metode Substitusix + y = 8 .... (1) y - x = 2 y = 2 + x.... (2) Substitusi pers (2) ke pers (1) y + x = 82 + x + x = 8 2 + 2x = 8 2x = 8 - 2 2x = 6 x = 6/2 x = 3Substitusi nilai x ke pers (2)y = 2 + xy = 2 + 3y = 5Hp = {3, 5}2. Metode Eliminasix + y = 8 .... (1) y - x = 2-x + y = 2 .... (2)Eliminasi x dari pers (1) dan (2) x + y = 8-x + y = 2_______ + 2y = 10 y = 10/2 y = 5Eliminasi y dari pers (1) dan (2) x + y = 8-x + y = 2_______ – 2x = 6 x = 6/2 x = 3Hp = {3, 5}3. Metode Grafikx + y = 8Titik potong sumbu x (y = 0) x + y = 8x + 0 = 8 x = 8 → tipot = (8, 0) Titik potong sumbu y (x = 0) x + y = 80 + y = 8 y = 8 → tipot = (0, 8) -x + y = 2Titik potong sumbu x (y = 0) -x + y = 2-x + 0 = 2 x = -2 → tipot = (-2, 0) Titik potong sumbu y (x = 0) -x + y = 2 0 + y = 2 y = 2 → tipot = (0, 2) Gambar terlampir di slide 1Bagian b1. Metode Substitusix - 2y = -1 x = 2y - 1 ....(1)2x + 3y = 12 .... (2)Substitusi pers (1) ke pers (2) 2x + 3y = 122(2y - 1) + 3y = 12 4y - 2 + 3y = 12 4y + 3y = 12 + 2 7y = 14 y = 14/7 y = 2Substitusi nilai y ke pers (1) x = 2y - 1x = 2(2) - 1x = 4 - 1x = 3Hp = {3, 2}2. Metode EliminasiEliminasi x dari pers (1) dan (2) x - 2y = -1 | ×2| 2x - 4y = -22x + 3y = 12 | ×1| 2x + 3y = 12 __________ – -7y = -14 y = 2Eliminasi y dari pers (1) dan (2) x - 2y = -1 | ×3| 3x - 6y = -32x + 3y = 12 | ×2| 4x + 6y = 24 __________ + 7x = 21 x = 3Hp = {3, 2}3. Metode Grafikx - 2y = -1Titik potong sumbu x (y = 0) x - 2y = -1x - 2(0) = -1 x - 0 = -1 x = -1 → tipot = (-1, 0) Titik potong sumbu y (x = 0) x - 2y = -10 - 2y = -1 y = ½ y = 0,5 → tipot = (0; 0,5) 2x + 3y = 12Titik potong sumbu x (y = 0) 2x + 3y = 122x + 3(0) = 12 2x = 12 x = 6 → tipot = (6, 0) Titik potong sumbu y (x = 0) 2x + 3y = 122(0) + 3y = 12 3y = 12 y = 4 → tipot = (0, 4) Gambar grafik terlampir pada slide kedua#LearnWithPanda](https://id-static.z-dn.net/files/d3f/e5a380fce45cff41c6463939059efcf8.jpg)
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Last Update: Mon, 06 Feb 23