SOLUTION: 3x2 -15x + 12 =

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Question 102753: 3x2 -15x + 12 =
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=3, b=-15, and c=12



Negate -15 to get 15



Square -15 to get 225 (note: remember when you square -15, you must square the negative as well. This is because .)



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 3 to get 6

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

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