Show that x = -1 is a zero of quadratic equation $x^{2}$ – 2x – 3 = 0

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Solution

The value of $x^{2}$ – 2x – 3 at x =-1 is ${- 1}^{2}$ – 2 × (-1) – 3 = 0

For x = -1, LHS = RHS

Hence, x = -1 is a zero of quadratic polynomial $x^{2}$ – 2x – 3.

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Show that x = -1 is a zero of quadratic equation x2– 2x – 3 = 0

The value of x2– 2x – 3 at x =-1 is −12 – 2 × (-1) – 3 = 0 For x = -1, LHS = RHS Hence, x = -1 is a zero of quadratic polynomial x2 – 2x – 3.

Show that x = -1 is a zero of quadratic equation $x^{2}$ – 2x – 3 = 0

The value of $x^{2}$ – 2x – 3 at x =-1 is ${- 1}^{2}$ – 2 × (-1) – 3 = 0

For x = -1, LHS = RHS

Hence, x = -1 is a zero of quadratic polynomial $x^{2}$ – 2x – 3.