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5 votes
What are the exact solutions of x^2 = 5x + 2?

1 Answer

3 votes
move everybody to one side
minus 5x+2 both sides
x^2-5x-2=0
use quadratic formula where
if you have
ax^2+bx+c=0
x=
\frac{-b+/- \sqrt{b^(2)-4ac} }{2a}

1x^2-5x-2=0
a=1
b=-5
c=-2

x=
\frac{-(-5)+/- \sqrt{(-5)^(2)-4(1)(-2)} }{2(1)}
x=
(5+/- √(25+8) )/(2)
x=
(5+/- √(33) )/(2)

aprox
x=5.372281323 or -0.3722813233
User Steven Brookes
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