Data Sufficiency

kwah wrote:Attached is a question from GMAT Prep Test 2.

Please advise how to achieve the result.

Answer: C

Thanks,
K

Distance between two points (x1, y1) and (x2, y2) is found by √([x2 - x1)² + (y2 - y1)²]
So, distance between (a, b) and (c, d) = √([a - c)² + (b - d)²]

(1) b - d = 4 implies we don't know a - c; NOT sufficient.
(2) a - c = 3 implies we don't know b - d; NOT sufficient.

Combining (1) and (2), required distance = √([a - c)² + (b - d)²] = √([3)² + (4)²]; SUFFICIENT

The correct answer is C.