CPM Homework Help : A2C Problem 7-219

Use matrices to solve these systems. Check your answers by substituting them in the original equations. You will not need a calculator if you use the results of the previous problem.

$p + 2q = 7 \\3p + 4q = 11$

Step 1(a):

First substitute matrices for the equations.

Step 2(a):

Multiply both sides by the inverse.

Step 3(a):

Solve for p and q.

$4m − 5n = −2 \\−3m + 4n = 9$
Hint (b):
See part (a).