Решите систему уравнений! ; ) 5х + 3 у = 380 380/х - 380/у = 19/6

5х + 3y = 380
( 380/x ) - ( 380/y ) = 19/6
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5x = 380 - 3y
x = 76 - 0,6y
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( 380y - 380x ) / xy = 19/6
6( 380y - 380x ) = 19xy
2280y - 2280x = 19xy
120y - 120x = xy
120y - 120( 76 - 0,6y ) = y( 76 - 0,6y )
120y - 9120 + 72y = 76y - 0,6y^2
192y - 9120 = 76y - 0,6y^2
0,6y^2 + 116y - 9120 = 0
D = 13456 + 21888 = 35344 = 188^2
y1 = ( - 116 + 188 ) : 1,2 = 60
y2 = ( - 116 - 188 ) : 1,2 = - 304 : 1,2 = - 3040/12 = - 760/3 = - 253 1/3
X = 76 - 0,6y
X1 = 76 - 36 = 40
X2 = 76 + ( 3/5 )•( 760/3 ) = 76 + ( 760/5 ) = 76 + 152 = 228
ответ ( 40 ; 60 ) ; ( 228 ; - 253 1/3 )