Serena made a scale drawing of her triangular flower garden. Two sides of her garden are 5m and 6m long and form an angle of 40 degrees. Serena drew a 40 degree angle on paper, marked points at 10 cm and 12 cm on the arms, and joined these points. She measured the third side to be 9.5 cm. How long is the third side of the garden?
Please explain how you did it! My teacher is teaching us the "cross-multiply and divide" trick to this chapter to figure out sides on two triangles. I also understand the standard "cross-product rule". Thanks for your help in advance.
Math problem? Similar Triangles?
triangular flower garden and the triangle on the paper are similar, so
5m/10cm = 6m/12cm = x/9.5cm
5m/10cm = x/9.5cm
5m * 9.5cm = x * 10cm
x = 5m * 9.5cm/10cm = 4.75 m
BTW, the measured length of the third side on the paper is not correct, which should be about 7.8 cm, so the third side of the garden should be about 3.9 m
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