Solve. x2 + 4x + 1 = 0

Question

theviper · Answer

Use quadratic formula:-$$\Huge{\color{blue}{-b \sqrt{b^2-4ac}\over2a}}$$

theviper · Answer

a=1, b=4, c=1
Put the values & get ur answer:)

anonymous · Answer

???

anonymous · Answer

-4$$-4\sqrt{b ^{2}}-4(1)(1)/2(1)$$

campbell_st · Answer

you need to general quadratic formula or you need to complete the square

the formula is $$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$

where a = 1, b = 4 and c = 1

or by completing the square 


let 

$$x^2 + 4x + 1 = 0$$

find $$(\frac{4}{2})^2 = 4$$

you need the constant term to be 4 

so add 3 to both sides

then  

$$x^2 + 4x + 4 = 3$$

factorise 

$$(x + 2)^2 = 3$$

take the square root of both sides

$$x + 2 = \pm \sqrt{3}$$

subtract 2 from both sides

$$x = -2 \pm \sqrt{3}$$