Question

x^2+4x-1=0 Solve the equation by taking square roots.

Answer 1

Use the quadratic formula

Answer 2

\[
\left\{\left\{x= -2-\sqrt{5}\right\},\left\{x=
\sqrt{5}-2\right\}\right\}

\]

Answer 3

how?

Answer 4

Everytime i try it doesn't work

Answer 5

nevermind! i made a slight error! silly me!

Answer 6

i got 0.24, -4.24

Answer 7

\[
x^2+4x-1=0\\
a=1\\
b=4\\
c=-1\\
\Delta =b^2-4ac= 16+4=20\\
\sqrt \Delta= \sqrt{20}= 2 \sqrt 5\\

x= \frac{ -b \pm \sqrt \Delta}{2 a}=\frac{-4\pm 2\sqrt{5}}{2}=-2\pm \sqrt 5
\]

Answer 8

Numerically the roots are
\[
{{x = -4.23607}, {x = 0.236068}}
\]
but you were asked to find the roots using square roots

Answer 9

k

Answer 10

thanks