Question

4.1) 4+( –y )= –y + 4
4.2) –3( x –4) =–3x +12​

Answer 1

4.1)

$4+( -y )= -y + 4\\4-y-4=-y+4-4\\-y=-y\\-y+y=-y+y\\0=0$

4.2)

$-3\left(x-4\right)=-3x+12\\-3x+12=-3x+12\\-3x+12-12=-3x+12-12\\-3x=-3x\\-3x+3x=-3x+3x\\0=0$