Question

In Right Angled Triangle ABC (B is right angle), Angle C is 15°, Angle A is 75° and Side BC is 22.5 then find AB​

Answer 1

Answer:

B

5AC2

Given, △ABC, M is mid point of AB and N is mid point of BC.

In △ABN,

AN2=AB2+BN2 (Pythagoras Theorem)

AN2=AB2+(2BC)2 ....(1)

In △BMC,

MC2=BM2+BC2 (Pythagoras Theorem)

MC2=BC2+(2AB)2 ....(2)

Add (1) and (2),

AN2+MC2=AB2+(2BC)2+BC2+(2AB)2

AN2+MC2=45AB2+45BC2

4(AN2+MC2)=5(AB2+BC2)

4(AN2+MC2)=5AC2 (Pythagoras Theorem in △ABC)

Step-by-step explanation:

I hope this is useful