Write an equation for a line perpendicular to y=7 that passes through the
point (2, 13).

Y=3x−1
General equation of line is y=mx+c
∴m=3
If two lines are perpendicular, thenm
1
​
⋅m
2
​
=−1
Slope of line perpendicular to y=3x−1 will be
3
−1
​

∴ Equation of line y=
3
−1
​
x+c
3y+x=c
This line passes through the point (1,2)
∴3(2)+1=c
c=7
Equation of line becomes
x+3y=7
x+3y−7=0

I’m confused as to what you are asking 66 2/3 percentage wise