SOLUTION: x^2-9x + 18 = 0

Question 98883:
x^2-9x + 18 = 0
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
Let's use the quadratic formula to solve for x:

Starting with the general quadratic

the general solution using the quadratic equation is:

So lets solve ( notice , , and )

Plug in a=1, b=9, and c=18

Square 9 to get 81

Multiply to get

Combine like terms in the radicand (everything under the square root)

Simplify the square root (note: If you need help with simplifying the square root, check out this solver)

Multiply 2 and 1 to get 2

So now the expression breaks down into two parts

or

Lets look at the first part:

Add the terms in the numerator
Divide

So one answer is

Now lets look at the second part:

Subtract the terms in the numerator
Divide

So another answer is

So our solutions are:
or

Notice when we graph , we get:

and we can see that the roots are and . This verifies our answer
RELATED QUESTIONS
x^2+9x+18=0 (answered by nerdybill)

X^2+18=9x (answered by mananth)

x^3+8x^2+9x-18=0 ;... (answered by josgarithmetic)

x^2-9x=0 (answered by checkley71)

x^2-9x=0 (answered by Menjax,jim_thompson5910)

Which is equivalent to sqrtx+2{+4}=3x A. 9x^2+x+18=0, where x >- -2 B. 9x^2-x-18=0,... (answered by texttutoring)

(x^2-9x+18)/(x-6) (answered by fractalier)

Divide. (x^2 + 9x + 18) � (x +... (answered by Fombitz)

Find all real or imaginary solutions to each equation. x^-2 - 9x^-1 + 18 =... (answered by stanbon)