Cos^4 (A/2)- sin^4(A/2)=cosA
1 answer:
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Answer:
ED: 6.5 cm BE = 14.4 cm
Step-by-step explanation:
Add 20 and 5 to get side AC.
25/20 gives us the scale factor to go from 25 triangle ABE to triangle ACD.
Multiply 26 by the SF to get AD.
Subtract length of AD by AE to get ED. You should get 6.5 cm (don't forget units!!!!)
To go from triangle ACD to triangle ABE, we can do 20/25 to get the scale factor.
Using that number, multiply it with 18 to get BE.
The answer should be 14.4 cm.
This is possible because the two triangles ACD and ABE are similar via the angle angle angle similarity theorem depicted in my screenshot.
