We have the equation
2x+y = 4
We need to find the slope so we rewrite the equation in slope intercept form y = mx+b where m is the slope and b is the y intercept
2x+y-2x = -2x+4
y = -2x +4
The slope is -2
Perpendicular lines have slopes that multiply to -1
-2 * m = -1
m = 1/2
The slope of a line that is perpendicular is 1/2
Using slope intercept form
y = mx+b and a slope of 1/2 and the y intercept of 1
y = 1/2x + 1
