Write the equation of a line that is perpendicular to y = 5 y=5y, equals, 5 and that passes through the point ( − 7 , − 5 ) (−7,−5)left parenthesis, minus, 7, comma, minus, 5, right parenthesis.

The line of the equation perpendicular to y=5 and cuts through (-5,-7) will be given by
m(x-x1)=y-y1
where m=slope.
from y=0x+5, the slope of the perpendicular line m=0,
thus the equation will be:
0(x--5)=y--7
0=y+7
y=-7
The equation is y=-7