# Math Help - Help solving the following system of equations by using the inverse of the coef

1. ## Help solving the following system of equations by using the inverse of the coef

7x - y + 7z = -10
8y+7z = 17
-7x+4y+6z = 6

I know i have to set something up like [a]^-1 [b] in the Ti but i am just having a ton of confusion here...

2. ## Re: Help solving the following system of equations by using the inverse of the coef

Originally Posted by Niaboc

7x - y + 7z = -10
8y+7z = 17
-7x+4y+6z = 6

I know i have to set something up like [a]^-1 [b] in the Ti but i am just having a ton of confusion here...
Yes, you need to set up \displaystyle \begin{align*} \left[ \begin{matrix} \phantom{-}7 & -1 & 7 \\ \phantom{-}0 & \phantom{-}8 & 7 \\ -7 & \phantom{-}4 &6 \end{matrix} \right]^{-1} \left[ \begin{matrix} -10 \\ \phantom{-}17 \\ \phantom{-}6 \end{matrix} \right] \end{align*}

3. ## Re: Help solving the following system of equations by using the inverse of the coef

When i got to that point i was lost because it gave me these long decimals my TI-83 is damaged so i couldn't see the answer....is it possible you could show me the fraction in the three part form.