Question

How do you solve using the quadratic formula method `2x^2 + 3x – 1 = 0`?

Answer 1

`x=(-3+sqrt17)/4` or `x=(-3-sqrt17)/4`

Explanation:

Quadratic formula which gives solution of `ax^2+bx+c=0`
is `x=(-b+-sqrt(b^2-4ac))/(2a)`.

In the equation `2x^2+3x–1=0`, `a=2`, `b=3` and `c=-1` and hence solution is

`x=(-3+-sqrt(3^2-4xx2xx(-1)))/(2xx2)`

or `x=(-3+-sqrt(9+8))/(2xx2)=-(3+-sqrt17)/4`

i.e. `x=(-3+sqrt17)/4` or `x=(-3-sqrt17)/4`