# How do you find the solution to the quadratic equation #x^2 - 4x -3 = 0#?

##### 3 Answers

#### Explanation:

#"there are no whole numbers which multiply to - 3"#

#"and sum to - 4"#

#"we can solve using the method of "color(blue)"completing the square"#

#"the coefficient of the "x^2" term is 1"#

#• " add subtract "(1/2"coefficient of the x-term")^2" to"#

#x^2-4x#

#rArrx^2+2(-2)xcolor(red)(+4)color(red)(-4)-3=0#

#rArr(x-2)^2-7=0#

#rArr(x-2)^2=7#

#color(blue)"take the square root of both sides"#

#rArrx-2=+-sqrt7larrcolor(blue)"note plus or minus"#

#rArrx=2+-sqrt7larrcolor(red)"exact solutions"#

x =

#### Explanation:

Apply quadratic formula for this equation instead of trying to factor it out.

1/

2/

3/

4/

5/ x =

#### Explanation:

Here,

OR

Comparing with quadratic equation,

So,