Explanation:
the slope of a line function is always the factor of x.
in our case : 2
it is the ratio y/x indicating how many units y changes, when x changes a certain amount of units.
in our case (2 = 2/1) y increases by 2 for every x increase by 1.
now, the perpendicular slope simply changes x and y upside-down and flips the sign.
in our case it is : -1/2
so, the line function looks like
y = (-1/2)x + b
b is the y-intercept, and we get it by using the coordinates of the point as x and y
6 = (-1/2)×0 + b = b
the full line equation is
y = (-1/2)x + 6