Find a missing side of similar triangles
Find the scale factor from the matching sides, then use it on the side you need.
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Triangle ABC is similar to triangle DEF. AB = 6 cm, BC = 3 cm and DE = 18 cm. How long is EF, in cm?
Answer: 9
Triangle ABC is similar to triangle DEF. AB = 7 cm, BC = 12 cm and DE = 14 cm. How long is EF, in cm?
Answer: 24
Triangle ABC is similar to triangle DEF. AB = 4 cm, BC = 9 cm and DE = 12 cm. How long is EF, in cm?
Answer: 27
Tip: Find the scale factor from the matching sides, then use it on the side you need.
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