Final answer:
To solve for x in the equation 70° + x + 55° = 60°, subtract 70° and 55° from both sides to get x = -65°.
Step-by-step explanation:
To solve for x in the equation 70° + x + 55° = 60°, we need to isolate x on one side of the equation. First, we subtract 70° and 55° from both sides to get x = 60° - 70° - 55°. Simplifying the equation, we have x = -65°. Therefore, the correct answer is (d) -5.