The diagram is made up of four congruent rectangles with dimensions 3 by 4.
Hide/Reveal Description of Diagram for Q11
The four rectangles are arranged side-by-side forming one larger rectangle. The left side of the large rectangle is labeled 4. The top (and bottom) is the total of four sides of length 3. A is the bottom left vertex of the large rectangle and B is the top right corner. A path is made up of line segments. It starts at A, moves diagonally up across the first rectangle, down the side shared by rectangles 1 and 2, across the bottoms of rectangles 2 and 3, up the shared side of rectangles 3 and 4, and the across the top of rectangle 4, ending at B.
What is the length of the path from A to B shown on the diagram?
Pick one
Solution
Since BCD is a straight line segment, then $∠ BCD =180°$.
Therefore, $∠ ACB =∠BCD−∠ACD=180°−75°=105°$.
Since the sum of the three angles in △ABC is 180°, then $∠ABC=180°−105°−35°=40°$.
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