The expression (11.98 x 11.98 + 11.98 x x + 0.02 x 0.02) will be a perfect square for x equal to:

• A. 0.0004
• B. 0.00004
• C. 0.04
• D. 0.004

Answer: (C)

Given expression = (11.98)² + (0.02)² + 11.98 x x.For the given expression to be a perfect square, we must have11.98 x x = 2 x 11.98 x 0.02 or x   = 0.04