# Maths help

“Given that the solutions of the equation 3x^2-12x-11=0 can be written as c +/- root d, where c and d are rational numbers. Find the value of c and d.”
So far I’ve found the completed square which is 3(x-2)^2-23 and I’ve found c to be 2

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Put your completed square form equal to 0. Now you have an equation with a single x you can solve for.
Original post by Luwei

I’ve already tried and gotten 1/root 3 and it says it’s wrong
Original post by Dancer2001
Put your completed square form equal to 0. Now you have an equation with a single x you can solve for.

I’ve already tried and gotten root 69 over 3 and it says it’s wrong
I’ve already tried and gotten root 69 over 3 and it says it’s wrong

Original post by mqb2766

The flipside is you're expected to show how you tried to get the solution.
Original post by mqb2766
The flipside is you're expected to show how you tried to get the solution.

This is what I did and it says it’s wrong but I don’t get how
This is what I did and it says it’s wrong but I don’t get how

You have sqrt(23/3)
What do you do then? What is d?
“Given that the solutions of the equation 3x^2-12x-11=0 can be written as c +/- root d, where c and d are rational numbers. Find the value of c and d.”
So far I’ve found the completed square which is 3(x-2)^2-23 and I’ve found c to be 2

Original post by mqb2766
You have sqrt(23/3)
What do you do then? What is d?

I did square root it and I got the square root of 69 over 3, and it says it’s incorrect

I did square root it and I got the square root of 69 over 3, and it says it’s incorrect

sqrt69)/3 is numerically the right amswer for c +/- d, but it asks for c +/- sqrt(d).
So I sqrt the sqrt of 69/3I just did that and I got 1.663993576, it asks for the answer to be in a fraction and it it’s simplest from
So I sqrt the sqrt of 69/3I just did that and I got 1.663993576, it asks for the answer to be in a fraction and it it’s simplest from

What is the fraction INSIDE the square root.
Original post by mqb2766
What is the fraction INSIDE the square root.

Original post by mqb2766
What is the fraction INSIDE the square root.

Sqrt69/3