Question

Choose the correct answer for the following question.

One of the roots of equation x² + mx – 5 = 0 is 2; find m.

Options

• -2

• `-1/2`

• `1/2`

• 2

Answer 1

For the equation, x² + mx – 5 = 0
one of the roots is 2. So, 2 should satisfy the given equation.

\[\left( 2 \right)^2 + m \times \left( 2 \right) - 5 = 0\]
\[ \Rightarrow 4 + 2m - 5 = 0\]
\[ \Rightarrow 2m - 1 = 0\]
\[ \Rightarrow m = \frac{1}{2}\]

Hence, the correct answer is `1/2`.