Răspuns:
Explicație pas cu pas:
5(x+4y)=8(x+2y) şi
7x+28y+5x+10y=162
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5x+20y=8x+16y
12x+38y=162
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-3x+4y=0, 3x=4y, x=4y/3
6x+17y=81
6*4y/3+17y=81, 25y=81, y=81/25
3x=4y, y=3x/4
6x+17*3x/4=81, 75x=324, x=324/75=108/25