Answer:
y=x+12
Explanation:
y=-x+12; is a line with slope m1=-1
to find perpendicular slope of intersecting line take the negative inverse of m1. so -1*(1/(-1))=1=m2
use equation for a line of y=m*x+b and put in the point (-5,7) and solve for b=the y axis intercept
7=1*(-5)+b
7=-5+b
12=b
so
y=x+12