Question

In each of the second degree polynomials given below, find the numbers to be taken as x to get zero:

(i) x² − 5x + 6

(ii) x² − 2x − 1

(iii) x² + 5x + 6

(iv) 2x² − 7x − 15

(v) x² + x − 6

(vi) 9x² + 12x + 4

(vii) x² − x − 6

Answer 1

(i)

_{The value of x obtained by equating the given polynomial to 0 is the required value of x.}

_∴

Comparing the above equation with general quadratic equation:

a = 1, b = −5 and c = 6

(ii)

_{The value of x obtained by equating the given polynomial to 0 is the required value of x.}

_∴

Comparing the above equation with general quadratic equation:

a = 1, b = −2 and c = −1

(iii)

_{The value of x obtained by equating the given polynomial to 0 is the required value of x.}

_∴

Comparing the above equation with general quadratic equation:

a = 1, b = 5 and c = 6

(iv)

_{The value of x obtained by equating the given polynomial to 0 is the required value of x.}

_∴

Comparing the above equation with general quadratic equation:

a = 2, b = −7 and c = −15

(v)

_{The value of x obtained by equating the given polynomial to 0 is the required value of x.}

_∴

Comparing the above equation with general quadratic equation:

a = 1, b = 1 and c = −6

(vi)

_{The value of x obtained by equating the given polynomial to 0 is the required value of x.}

_∴

Comparing the above equation with general quadratic equation:

a = 9, b = 12 and c = 4

(vii)

_{The value of x obtained by equating the given polynomial to 0 is the required value of x.}

_∴

Comparing the above equation with general quadratic equation:

a = 1, b = −1 and c = −6