metode subtitusi 4x-y=5 dan x-3y=-7

Persamaan linear Dua variabel
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¤Metode Substitusi

=> 4x - y = 5
=> x - 3y = -7 -----> x = -7 + 3y

4x - y = 5
4(-7 + 3y) - y = 5
-28 + 12y - y = 5
11y = 5 + 28
11y = 33
y = 33/11
y = 3

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

Hp = { 2,3 }

4x - y = 5 ... pers.1
→ y = 4x - 5 ...pers.1'

x - 3y = -7 ...pers.2
→x = 3y - 7 ...pers.2'

Substitusikan pers.1' ke pers.2
x - 3y = -7
x - 3(4x - 5) = -7
x - (12x - 15) = -7
x - 12x + 15= -7
x - 12x = -7 - 15
-11x = -22
x = (-22) ÷ (-11)
x = 2

Substitusikan pers.2' ke pers.1
4x - y = 5
4(3y - 7) - y = 5
12y - 28 - y = 5
12y - y = 5 + 28
11y = 33
y = 33 ÷ 11
y = 3

HP = {2, 3}