Respuesta :

eah
Hi Meep21

3(7x - 9) - 19x = - 15
21x - 27 - 19x = - 15
2x = 27 - 15
2x = 12
x = 12 / 2
x = 6

S = {6}
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x + 3(x - 7) = 19
x + 3x - 21 = 19
4x = 19 + 21
4x = 40
x = 40 / 4 
x = 10

S= {10}