Solve the following quadratic equation SHOW WORK/EXPLAIN?

Question

x² -6x = 216

I know how to factor it's just that 216 is a big freaking # I can't break it down, and even more harder is when I ever I get a number that matches I need to subtract so I can get "6" IMPOSSSIBLE!

Answer 1

no problemoooooooooo

12 and 18 do the job :D

x^2-6x-216=0

(x-18)(x+12)=0

x=18 or x=-12

hope i helped

Answer 2

x² - 6x = 216

Do you know the quadratic formula? If you're finding it difficult to factor, you can always just use the quadratic formula.

x² - 6x - 216 = 0

x = [ -b +/- sqrt(b^2 - 4ac) ] / (2a)

x = [ 6 +/- sqrt(36 - 4(1)(-216) ] / (2)

x = [ 6 +/- sqrt(36 + 864) ] / (2)

x = [ 6 +/- sqrt(900) ] / 2

x = [ 6 +/- 30 ] / 2

x = 3 +/- 15

Therefore,

x = { 3 + 15, 3 - 15 }

x = { 18, -12 }

Which implies this would have factor as

(x - 18)(x + 12) = 0

{Not that this would matter now that you've found the solutions}

Answer 3

X^2 -6X -216 = 0

X = (6+ sqr [36 - (4x1x -216)] )/2
= (6+ sqr [36 + 864])/2
= (6+ sqr 900)/2
= 36/2 = 18

or this is another solution for the same equation
X = (6- sqr [36 - (4x1x -216)] )/2
= (6- sqr [36 + 864])/2
= (6- sqr 900)/2
= -24/2 = -12

i don't know why you need to do subtract and get six but you can do it:
just subtract 18-12 =6

Answer 4

This is a complete the square problem.
x^2 - 6x = 216
x^2 -6x + 9 = 216 + 9
(You add 9 to each side to make x^2-6x into a perfect square)
x^2 - 6x +9 = 225
(x-3)^2 = 15^2
x-3 = +/- 15
x = 3+15; 3-15
x = 18; -12

Answer 5

answer: (x+12)(x-18)

you re-arrange so that it's equal to 0, then factorise, so:

x^2 - 6x - 216 = 0

then you know that

(x + ?)(x - ?) = 0

you kind of have to guess what the?'s are, but you know they both add up to -6, and they multiply to give -216, and 12 and -18 fit, so:

(x+12)(x-18) = 0

then you know that either

x +12 = 0 OR x-18 = 0

(because anything multiplied by 0 gives 0)

So: x = -12 Or x = 18

easy!