In triangle ABC, DEAC. If AD=12, BD=3, and CE=10, find BE.
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Answer:
BE = 2.5
Step-by-step explanation:
Remark
Use triangles ABC and DEB.
Formula
AB/DB = BC / BE
Givens
Solution
15/3 = (10 + x)/x Cross multiply
15x = 3(10 + x) Remove the brackets
15x = 30 + 3x Subtract 3x from both sides.
15x - 3x = 30 Combine
12x = 30 Divide by 12
x = 30/12
x = 2.5