Question

1. Dikethui sistem persamaan linear x+y =6
x+3y=2
Himpunan penyelesaian{x,y}adalah...

2. Jika x dan y adlah penyelsaian dri sistem persamaan 7x + 2y =19 dan 4x-3y=15, nilai 3x-2y adalah...

Answer 1

1. x + y = 6     * 3
x + 3y = 2    * 1

3x + 3y = 18
x + 3y = 2
2x = 16
x = 8

x + y = 6
8 + y = 6
y = -2

2. 7x + 2y = 19   *3
4x - 3y = 15   *2

21x + 6y = 57
8x - 6y = 30
29x = 87
x=3

4x - 3y = 15
12 - 3y = 15-
3y = 3
y = -1
3x - 2y
9 - (-2) = 11

maaf kalau salah