Select the number that will come in place of the question mark (?) in the following mathematical statement.
49 × 57 - 41 × 18 = (?)2 × 3 + 1380
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 15
49 × 57 1 41 × 18 = (x²) × 3 + 1380
2793 - 738 = x2 × 3 + 1380
2055 = 3x² + 1380
2055 – 1380 = 3x²
675/3 = x²
675 = x²
225 = x²
x = √ 225
x = 15