Предмет: Математика, автор: михаил209

как решить систему пожалуйста

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Автор ответа: 987oiu789
0

(a+c)x-(a-c)y=2ab
(a+b)x-(a-b)y=2ac

аx+cx-ay+cy=2ab
ax+bx-ay+by=2ac

ax-ax+cx-bx-ay+ay+cy-by=2ab-2ac
x(c-b)+y(c-b)=2a(b-c)
(c-b)(x+y+2a)=0
 система может иметь корни при выполнении хотя бы одного из двух условий:
1)   c-b=0  при  b=c
система имеет бесконечное множество решений, так как исходные уравнения совпадают
2)   
x+y+2a=0
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