(х+3)(х-7)-(8-4)(х+4)=11 ПОМОГИТЕ ПЛИИЗЗЗЗЗ СИТЕМА х-у=3 2х-3у=4

( x + 3 )( x - 7 ) - ( 8 - 4)( x + 4 ) = 11
x² - 7x + 3x - 21 - 4( x + 4 ) = 11
x² - 4x - 21 - 4x - 16 = 11
x² - 8x - 48 = 0
D = 64 + 192 = 256 = 16²
x1 = ( 8 + 16 ) : 2 = 12
x2 = ( 8 - 16 ) : 2 = - 4
ОТВЕТ (12 ; - 4 )
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x = y + 3
2( y + 3 ) - 3y = 4
2y + 6 - 3y = 4
- y = - 2
y = 2
x = 2 + 3 = 5
ОТВЕТ ( 5 ; 2 )