Question

Selesaikan dari sistem persamaan 3x+y= -1 dan x+3y=5 adalah

Answer 1

Verified answer

3x + y = - 1
y = - 3x - 1
disubtitusi ke pers :
x + 3y = 5
x + 3(-3x - 1) = 5
x - 9x - 3 = 5
- 8x = 5 + 3
- 8x = 8
x = - 1
disubtitusi ke pers :
y = - 3x - 1
y = - 3(-1) - 1
y = 3 - 1
y = 2
hp = ( - 1 , 2)

Answer 2

Verified answer

3x + y = -1
y = -1 - 3x

x + 3y = 5
x + 3 (-1 - 3x) = 5
x - 3 - 9x = 5
-8x = 8
x = 8 : (-8)
x = -1

y = -1 - 3x
y = -1 - 3(-1)
y = -1 + 3
y = 2

Himpunan Penyelesaian = (-1 , 2)