Question

The coefficient of x² in x² + 2x + 9 = `3x(x/2 - 1)` is ______.

Options

• `1/2`

• 1

• 2

• `3/2`

Answer 1

The coefficient of x² in x² + 2x + 9 = `3x(x/2 - 1)` is `underline(1/2)`.

Explanation:

The given equation is, x² + 2x + 9 = `3x(x/2 - 1)`

⇒ x² + 2x + 9 = `(3x^2)/2 - 3x`

⇒ `x^2 - (3x^2)/2 + 2x + 3x + 9` = 0

⇒ `- x^2/2 + 5x + 9` = 0

⇒ `x^2/2 - 5x - 9` = 0

On comparing the above equation with the standard quadratic equation ax² + bx + c = 0, we get

a = `1/2` , b = – 5, c = – 9

Thus, the coefficient of x² is `1/2`.