Exam question help

[abzzzz]

How do you do graphs and relations q9 from vcaa 2010 exam 1

[ceekayx]

The point where both of the line intersects is going to = b (also Length)
but in order to make the first line  1/2 * length + 3 to intersect it needs to shift down 1m.
so the new equation formed is :
1/2 *L+3-1

then the second equation remains the same:
-1/6*L+5

Then equate them together and solve for L
1/2*L+3-1=-1/6*L+5

you should get L=4.5