given: △abc, d∈ac
m∠bdc=m∠abc
ad=7, dc=9
find: bc, bd/ba

Step-by-step explanation:

Given: △ABC, D∈AC , m∠BDC=m∠ABC , AD=7, DC=9.

Solution: Let BC=x, From the given figure and the given information, it can be seen that △ABC is similar to ΔBDC by AA rule, thus using the proportionality theorem, we get

⇒

⇒

⇒

⇒BC=12

Now, calculate the similarity scale,

k=

=

Therefore,

⇒

⇒

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step-by-step explanation: