1. The problem statement, all variables and given/known data Kindly view my 1st attachment. I need help to get the intersection of the highest line and the line extended by a slope from the horizontal line. 2. Relevant equations y=mx+b y-y1=m(x-x1) 3. The attempt at a solution Kindly view my 2nd attachment. By substitution, I always get the answer -1.87 which is obviously wrong. The answer should be lesser than -5.5. Thanks in advance.