Distribute the Negative sign
= -1/2x+6/7 +-1 ( 7/2 x - 4/7)
= -1/2 x + 6/7 +-1(7/2 x ) +-1 (-4/7)
= -1/2 x +6/7 + -7/2 x +4/7
Combine like terms
-1/2 x +6/7 + -7/2 x +4/7
( -1/2 x + -7/2 x ) + ( 6/7 +4/7 )
= -4x + 10/7
I hope that's help !
