SOLUTION: Pls help me solve this question x2+12x+36=0

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Question 1068009: Pls help me solve this question x2+12x+36=0
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
you can factor this as follows.

first put it in standard form of ax^2 + bx + c = 0

it's already in that form.

you get:

a = 1
b = 12
c = 36

your answers, if there are any that you can find that are rational, will be a factor of a * c which is equal to 36.

36 is equal to 1 * 36 or 2 * 18 or 3 * 12 or 4 * 9 or 6 * 6.

if you add these factors together, the last one (6 * 6) will be equal to 12.

this means your factors are (x + 6) * (x + 6) = 0

solve for x in each of there and you gert x = -6 or x = -6.

the roots of that equation are x = - 6.

if you graph that equaiton, you will see that it touches the x-axis at x = -6 only.

here's what the graph looks like.

$$$


here's a good link on how to factor quadratic equations.

http://www.purplemath.com/modules/factquad.htm