Jawab dengan serius Tentukan SPLDV berikut menggunakan metode gabungan(eliminasi-subtitusi) A.)0,25x + 0,25y = 3 0,75x + 0,125y= 2 B.)0,5x + 0,6y = -2 1,5x - 0,

SPLDV


1||

Eliminasi

0,25x + 0,25y   = 3   |x0,5|   0,125x + 0,125y = 1,5
0,75x + 0,125y = 2   |x1|      0,75x   + 0,125y = 2
------------------------- -            ------------------------------ -
                                                          -0,625x = -0,5
                                                                    x = 0,8

Subtitusi

       0,25x + 0,25y = 3
0,25 (0,8) + 0,25y = 3
           0,2 + 0,25y = 3
                    0,25y = 2,8
                          y = 11,2



2||

Eliminasi

0,5x + 0,6y = -2     |x 0,8|  0,4x + 0,48y = -1,6
1,5x - 0,8y  = 7      |x 0,6|  0,9x - 0,48y  = 4,2
---------------------- +            --------------------------- +
                                                       1,3x = 2,6
                                                            x = 2

Subtitusi

0,5x + 0,6y = -2
0,5 (2) + 0,6y = -2
1 + 0,6y = -2
      0,6y = -3
           y = -5

Eliminasi = pengurangan
Substitusi = substitusi variabel

1. ELIMINASI

#a
0,25x + 0,25y = 3
<=> 0,75x + 0,75y = 9

0,75x + 0,75y = 9
0,75x + 0,125y = 2
-------------------------- -
0,625y = 7
y = 11,2
x = 0,8

#b
0,5x + 0,6y = -2
<=> 1,5x + 1,8y = -6

1,5x - 0,8y = 7
1,5x + 1,8y = -6
---------------------- -
-2,6y = 13
y = -5
x = 10

2. SUBSTITUSI

#a
0,25x + 0,25y = 3
<=> 0,25x = 3 - 0,25y
<=> 0,75x = 9 - 0,75y

0,75x + 0,125y = 2
<=> 9 - 0,75y + 0,125y = 2
<=> 9 - 0,625y = 2
<=> 9 - 2 = 0,625y
<=> 7 = 0,625y
y = 11,2
x = 0,8

#b
0,5x + 0,6y = -2
<=> 0,5x = -2 + (-0,6y)
<=> 1,5x = -6 - 1,8y

1,5x - 0,8y = 7
<=> -6 - 1,8y - 0,8y = 7
<=> -2,6y = 7 + 6
<=> -2,6y = 13
y = -5
x = 10