Question

Complete the square: (x - 4)^2 = 49 (I'd like help, not answers) =)

Answer 1

This is just a practice question, but I don't know how to do it and can't find anything in the lesson

Answer 2

The first thing you would do in this equation is find the square root of both sides. Since x-4 is in parentheses, x-4 is left.
x-4=sq.root(-49). Since it is impossible to do the square root of negative numbers, the imaginary number, i , is used.
i=sq.root(-1)
7 comes out of -49, and -1 is left under the radical. Since i equals -1, x-4=(plus or minus)7i
Since we found the square root of -49, there are two possible x values, positive 7i and negative 7i.
Add 4 to each side to isolate the x variable.
x=4(plus/minus)7i