tentukan himpunan penyelesaian sistem persamaan berikut dengan metode eliminasi 1. 2x+5y+8=0 3x=-4y_5

2x+5y+8=0
3x=-4y-5

Jawab:
2x + 5y + 8 = 0 (.3)
3x + 4y + 5 = 0 (.2)

6x + 15y + 24 = 0
6x + 8y + 10 = 0
-------------------------- -
7y + 14 = 0
7y = -14
y = -14/7
y = -2

2x + 5y + 8 = 0 (.4)
3x + 4y + 5 = 0 (.5)

8x + 20y + 32 = 0
15x + 20y + 25 = 0
---------------------------- -
-7x + 7 = 0
-7x = -7
x = -7/-7
x = 1

x = 1
y = -2