Chapter 8: Problem 66
What is the fastest method for solving a linear system with your graphing utility?
Short Answer
Step by step solution
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none}
Learning Materials
Features
Discover
Chapter 8: Problem 66
What is the fastest method for solving a linear system with your graphing utility?
These are the key concepts you need to understand to accurately answer the question.
All the tools & learning materials you need for study success - in one app.
Get started for free
Write each linear system as a matrix equation in the form \(A X=B,\) where \(A\) is the coefficient matrix and \(B\) is the constant matrix. $$\left\\{\begin{array}{l} 7 x+5 y=23 \\ 3 x+2 y=10 \end{array}\right.$$
Use the fact that if \(A=\left[\begin{array}{ll}a & b \\ c & d\end{array}\right],\) then \(A^{-1}=\frac{1}{a d-b c}\left[\begin{array}{rr}d & -b \\ -c & a\end{array}\right]\) to find the inverse of each matrix, if possible. Check that \(A A^{-1}=I_{2}\) and \(A^{-1} A=I_{2}\) $$A=\left[\begin{array}{rr} 3 & -1 \\ -4 & 2 \end{array}\right]$$
Low-resolution digital photographs use \(262,144\) pixels in a \(512 \times 512\) grid. If you enlarge a low-resolution digital photograph enough, describe what will happen.
Use the fact that if \(A=\left[\begin{array}{ll}a & b \\ c & d\end{array}\right],\) then \(A^{-1}=\frac{1}{a d-b c}\left[\begin{array}{rr}d & -b \\ -c & a\end{array}\right]\) to find the inverse of each matrix, if possible. Check that \(A A^{-1}=I_{2}\) and \(A^{-1} A=I_{2}\) $$A=\left[\begin{array}{rr} 2 & 3 \\ -1 & 2 \end{array}\right]$$
Write each system in the form \(A X=B .\) Then solve the system by entering \(A\) and \(B\) into your graphing utility and computing \(A^{-1} B\). $$\left\\{\begin{array}{rr}v-3 x+z= & -3 \\\w+x+y & =-1 \\\x+w-x+4 y & =7 \\\v+w-x+4 y & =-8 \\\v+w+x+y+z= & 8\end{array}\right.$$
What do you think about this solution?
We value your feedback to improve our textbook solutions.