EXAMPLE 2 Solve a matrix equation SOLUTION Begin by finding the inverse of A = Solve the matrix equation AX = B for the 2 × 2 matrix X. 2 –7 –1 4 – –2 A B X = A –1 = 1 8 –
EXAMPLE 2 Solve a matrix equation To solve the equation for X, multiply both sides of the equation by A – 1 on the left. A –1 AX = A –1 B IX = A –1 B X = A –1 B X = 0 –2 3 – – –2 = 2 –7 – X X –2 3 –1 =
GUIDED PRACTICE for Example 2 4. Solve the matrix equation – X = –1 –2 4 1 ANSWER