Решите уровнения надо ответ чему равен х1 и х2 1)7x^2-54x+35=0 2)-3x^2-28x-49=0 3)-3^2+19x-28=0

7X^2 - 54X + 35 = 0
D = 2916 - 980 = 1936 ; √ D = 44 
X1 = ( 54 + 44 ) : 14 = 7
X2 = ( 54 - 44 ) : 14 = 2/7 

- 3X^2 - 28X - 49 = 0
D = 784 - 588 = 196 ; √ D = 14
X1 = ( 28 + 14 ) : ( - 6 ) = ( - 7 )
X2 = ( 28 - 14 ) : ( - 6) = ( - 7/3 ) = ( - 2 1/3 ) 

- 3X^2 + 19X - 28 = 0
D = 361 - 336 = 25 ; √ D = 5 
X1 = ( - 19 + 5 ) : ( - 6 ) = 7/3 = 2 1/3 
X2 = ( - 19 - 5 ) : ( - 6 ) = 4