Question

Complete the square: x^2 +6x +c

Answer 1

You want to put this in the form (x+b)^2 + c  

To do this take half of the coefficient of b from the ordinal form which is 6/2=3 as use this as your new b

This give you (x+3)^2.  

If you foil this out you get x^2 +6x +9 so you have added 9 to the original expression so now all you need to do is subtract 9 to keep things balanced  

The final expression then is (x+3)^2 -9

So c= -9

Answer 2

Answer:

c=√(c+9)-3

Step-by-step explanation:

x²+6x=-c

x²+6x+(3)²=-c+(3)²

(x+3)²=-c+9(find the square root of both sides)

√(x+3)²=√(c+9

x+3=√(c+9)

c=√(c+9)-3