Use the quadratic formula to find the exact solutions of x2 − 5x − 2 = 0.





Answer:
Solutions given:
given equation is
x²-5x-2=0
comparing above equation with ax²+bx+c,we get
a=1
b=-5
c=-2
By using quadratic equation
x=[tex] \frac{ - b± \sqrt{ {b}^{2} - 4ac} }{2a} [/tex]
x=[tex] \frac{ 5± \sqrt{ {-5}^{2} - 4*1*-2}}{2*1} [/tex]
x=[tex] \frac{ 5± \sqrt{ 25+8}}{2*1} [/tex]
x=[tex] \frac{ 5± \sqrt{ 33 }}{2} [/tex] is a required answer.
Answer:
[tex]x=\dfrac{5 \pm \sqrt{33}}{2}[/tex]
Step-by-step explanation:
Quadratic Formula
[tex]x=\dfrac{-b \pm \sqrt{b^2-4ac} }{2a}\quad\textsf{when }\:ax^2+bx+c=0[/tex]
Given equation:
[tex]x^2-5x-2=0[/tex]
Comparing the given equation with [tex]ax^2+bx+c=0[/tex] to find the values of a, b and c:
Substitute these values into the quadratic formula and solve for x:
[tex]\implies x=\dfrac{-(-5) \pm \sqrt{(-5)^2-4(1)(-2)}}{2(1)}[/tex]
[tex]\implies x=\dfrac{5 \pm \sqrt{25+8}}{2}[/tex]
[tex]\implies x=\dfrac{5 \pm \sqrt{33}}{2}[/tex]