Question

Which of the following is a quadratic equation?

• A. \( (x+1)(x-1) = x^2 - 4x^3 \)
• B. \( (x+4)^2 = 3x + 4 \)
• C. \( 4x + \frac{1}{2x} = 8x^2 \)
• D. \( (2x^2 + 4) = (5+x)(2x-3) \)

Hint:

A quadratic equation must have the highest power of \( x \) as 2.

Answer 1

The Correct Option is B

A quadratic equation is of the form:
\[ ax^2 + bx + c = 0. \]8 Expanding: \[ (x+4)^2 = 3x + 4. \] \[ x^2 + 8x + 16 = 3x + 4. \] \[ x^2 + 8x + 16 - 3x - 4 = 0. \] \[ x^2 + 5x + 12 = 0. \] This is a quadratic equation.