Предмет: Математика, автор: Vitiaaaa

Решите систему уравнений методом подстановки
X2+y2=20
3x+y=2

Ответы

Автор ответа: lakOR555
0
у=2-3х
х²+(2-3х)²=20
х²+4-12х+9х²-20=0
10х²-12х-16=0
5х²-6х-8=0
дискриминант = 36+160=196
√196=14
х1=6-14/10=-8/10=-0,8
х2=20/10=2

если х1=-0,8, то у=2+2,4=4,4
если х2=2, то у=2-6=-4
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