OG16- DS 98
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- Brent@GMATPrepNow
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There's a good discussion about this question here: https://www.beatthegmat.com/og-79-t111789.html
Cheers,
Brent
Cheers,
Brent
- OptimusPrep
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Area (ABC) = 1/2*AC*BC
Area (DBA) = 1/2*DA*AB
Statement 1:
AC = √2* AD. But we do not know anything about the base
ISUFFICIENT
Statement 2:
We just have the information about ABC
INSUFFICIENT
Combining both statements:
On combining, AC = CB, and AC = √2*AD
AB = AC^2 + BC^2 = 2AD + 2AD = 4AD
We have the values of base and perpendicular of both triangles in terms of AD.
Hence we can calculate and compare the area
SUFFICIENT
Correct Option: C