CPM Homework Help : A2C Problem 7-202

Represent each system of equations below with matrices. You do not have to solve the systems. Homework Help ✎
1. p + 2q = 7
  3p + 4q = 11
2. 4m − 5n = −2
  −3m + 4n = 9
3. 4x − y + z = −5
  2x + 2y + 3z = 10
  5x − 2y + 6z = 1
4. 7w − 3x + 2z = 41
  −2w + x − z = −13
  4w + y − 2z = 12
  2 − 3x = 1

Answer (a):

$\begin{bmatrix} 1&2\\ 3&4 \end{bmatrix}\begin{bmatrix} p\\ q \end{bmatrix}=\begin{bmatrix} 7\\ 11 \end{bmatrix}$

Hint (b):

See part (a).

Answer (c):

Hint (d):

See parts (a) and (c); rearranging the equations so the variables are in the same order helps.
Notice that there are four variables in total;filling in 0's for the missing variables is also helpful.