tentukan himpunan penyelesaian dari sistem persamaan berikut menggunakan cara subtitusi a. y= x + 5 dan 2x + y = 17 b. x= 6 - y dan 3x - y = 6 c. 2y = x - 8 dan

Nomor A :
y = x + 5

2x + y = 17
2x + (x + 5) = 17
3x + 5 = 17
3x = 17 - 5
x =12/3
x = 4

y = 4 + 5
y = 9

HP = {4,9)

Nomor B :
x = 6 - y

3x - y = 6
3 (6 - y) - y = 6
18 - 3y - y = 6
18 - 4y = 6
-4y = 6 - 18
-4y = -12
y = -12/-4
y = 3

x = 6 - y
x = 6 - 3
x = 3

HP = {3,3}

Nomor C :
2y = x - 8
x = 2y + 8

x + 2y = 10
2y + 8 + 2y = 10
4y + 8 = 10
4y = 10 - 8
y = 2/4
y = 1/2

x = 2y + 8
x = 2 (1/2) + 8
x = 1 + 8
x = 9

HP = {9,1/2}