Answer
$y=2x+4.$
Work Step by Step
If two lines are parallel then their slopes must be equal.
We know that if the slope of a line is $m$ and it contains $P_1(x_1,y_1)$, then its equation is: $y-y_1=m(x-x_1).$ It is parallel to $y=2x$, hence its slope is $m=2$. Hence here: $y-2=2(x-(-1))\\y-2=2x+2\\y=2x+4.$
