7. Substitute 'z', 'w', and 'x' into Eq. (2) to find 'y': \
Step 1 :1. Eliminate 'y' by adding Eq. (1) and Eq. (2): \
Step 2 :2. Eliminate 'y' by adding Eq. (1) and Eq. (3): \
Step 3 :3. Combine Eq. (4) and Eq. (5) to eliminate 'x' and solve for 'z': \
Step 4 :4. Substitute 'z' from Eq. (6) into Eq. (4) and solve for 'w': \
Step 5 :5. Substitute 'w' into Eq. (6) to find 'z': \
Step 6 :6. Substitute 'z' and 'w' into Eq. (1) to find 'x': \
Step 7 :7. Substitute 'z', 'w', and 'x' into Eq. (2) to find 'y': \