Question

x(x+12)=-28
I got (x+6)=-28. Is this correct? Please and Thank you.

Answer 1

@kitsune0724 Are you supposed to solve the given equation for x?

Answer 2

nope

first multiply and then simplify and then

Answer 3

@Directrix No you are suppose to find what would give the middle of the problem.

Answer 4

@kitsune0724 I don't know what you mean by "middle of the problem."

x(x+12)=-28
x^2 + 12x = -28
x^2 + 12x + 28 = 0
After that, I don't know what to say because I don't know the "middle."

Answer 5

@Directrix would it be like this (x-12)^2=-28?

Answer 6

@kitsune0724 I don't know because I don't understand what we are supposed to be doing. We need the directions / instructions for the problem.

Answer 7

@Directrix Which of the following equations is equivalent to the equation in exercise 30? (In
other words, which of these is an equation you should get in the MIDDLE of the
completing the square process?) this is the problem.

Answer 8

Oh...You complete the square...

Answer 9

He forgot the ^2

Answer 10

x(x+12)=-28
x^2 + 12x = -28
x^2 + 12x + 36 = -28 + 36
(x + 6)* (x+6) = 8 -----> Do you think we've made it to the middle yet. @kitsune0724

Answer 11

@Directrix yes. that's what I got so far.

Answer 12

(x + 6)* (x+6) = 8
(x + 6) = sqrt(8) OR (x + 6) = - sqrt (8) @kitsune0724

Answer 13

@Directrix (x + 6) = - sqrt (8).

Answer 14

@kitsune0724 What about this--> (x + 6) = sqrt(8)
It is one of the two roots.

Answer 15

@Directrix would it be x=6+2sqrt2, 6-2sqrt2?

Answer 16

Not quite. I think you have a sign error.

(x + 6) = sqrt(8) OR (x + 6) = - sqrt (8) @kitsune0724
x = -6 + sqrt(8) OR x = -6 - sqrt (8)
x = -6 + 2sqrt2 or x = -6 -2sqrt2

Answer 17

@Directrix x=-6+2sqrt2, -6-2sqrt2? I'm getting a bit confused here. Can you please draw it out for so I can what I'm doing wrong? Thank you.

Answer 18

We're just subtracting 6 from both sides to solve for x.

For example, (x + 6) = - sqrt (8). Subtract 6 from both sides.
x+6 - 6 = -sqrt(8) - 6
x + 0 = -6 - sqrt(8)
x = -6 - 2sqrt2

Same thinking for the second root. @kitsune0724