what should I do ? Where it’s say ‘ start here ‘?
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Yes, you are going to start the maze in the box that says "Start Here". For the first box we are trying to find the length of AB. Notice that AB + BC = AC. If we substitute our known values for AB and BC, we find that we obtain the equation:
[tex]2x + 4x = 12[/tex]
By simplifying our equation and isolating [tex]x[/tex], we can find our answer:
[tex]6x = 12[/tex]
[tex]x = 2[/tex]
[tex]AB = 2x = 4[/tex]
The length of AB is 4.