Solve x^2+6x+1=0 by completing the square

x2+6x+5=0 First of all half the x coefficient and write (x+6/2)2 the take away the (6/2)2 and add on the 5
(x+3)2-9+5=0
(x+3)2-4=0 Simplify the expression
(x+3)2=4 Move 4 to the other side of the equation so you can square root both sides
x+3=+-2 Take the square root of both sides
x=-5, x=-1 Take 3 away from both sides to find the 2 values of x that solve the equation

Answered by Ben S. Maths tutor

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