The reason is that the coordinates of C is (-2, -3). When it was shifted 6 units to the right and one up it means that -2 is added with 6 which is 4. Furthermore -3 plus 1 is -2 which makes the new coordinates at (4, -2).
This can be solved by imagining the triangle formed by the building and its shadow. The hypotenuse of the triangle, the distance from the tip of the building to the tip of the shadow, is 34 meters, and one of the legs is 29 meters. Therefore, we can use the Pythagorean theorem to find that the third side is . Hope this helps!
