2x . ( 5 - 3x ) + 2x . ( 3-5) - 3 . ( x - 7 ) = 3
10x - \(6x^2\)+ 2x. ( -3 ) - 3 .( x - 7 ) = 3
10 x \(-6x^2\)- 6x -3x + 21 = 3
x - \(6x^2\)= 3 - 21
x- \(6x^2\)=-24
x . ( 1-6x ) = -24
th1 :
x = -24
th2 : 1 - \(6x\)= -24
6x = 1 - - 24
6x = 25
x = \(\frac{25}{6}\)
lik - e nha