# Help please... Precalculus problem using matrices

by uselessjack
Tags: matrix matrices
 Mentor P: 21,215 For a, you want to solve the matrix equation Ax = y $$\left[ \begin{array} {c c c } 5 & 3 & 5 \\ 6 & 4 & 6 \\ 5 & 4 & 6 \end{array} \right]\left[ \begin{array}{c}x_1\\x_2\\x_3\end{array} \right] = \left[ \begin{array}{c}23\\28\\27\end{array} \right]$$ Using your inverse, A-1, can you figure out how to solve for the vector x? For b, similar setup, but the vector on the right uses the three values of this part of the problem.
 Quote by Mark44 For a, you want to solve the matrix equation Ax = y $$\left[ \begin{array} {c c c } 5 & 3 & 5 \\ 6 & 4 & 6 \\ 5 & 4 & 6 \end{array} \right]\left[ \begin{array}{c}x_1\\x_2\\x_3\end{array} \right] = \left[ \begin{array}{c}23\\28\\27\end{array} \right]$$ Using your inverse, A-1, can you figure out how to solve for the vector x? For b, similar setup, but the vector on the right uses the three values of this part of the problem.