Question

which of the following is a quadratic equation? Write it in the standard form. (c) (k+1)x^2+3/2x=7,where k=-1​

Answer 1

$If \: ax^{2}+bx+c=0 \: be \: a \: quadratic \\ equation, \: then \: it \: must \: be \\ understood \: that \: a cannot \: be \\ 0 , because \: when \: a=0 \: , the \\ coefficient \: of \: the \: square \: term \\ vanishes \: and \: this \: makes \: the \\ equation \: a \: linear \: equation \: of \: the \\ form \: bx+c=0$

$Given: the \: equation \: (k+1)x^{2}+\frac{3}{2}x = 7 \: is \: a \: quadratic \: equation$

To find: the value of k

Solution:

$Since (k+1)x^{2}+\frac{3}{2}x=7$

is a quadratic equation, the coefficient of the

$leading \: term \: x^{2}$

can not be zero.

$i.e., k+1\neq 0$

$\Rightarrow k\neq -1$

$Answer: k\neq -1$